4.1 Equivalent proportions

Transcription

1 4 Fractions, decimals and percentages Master Check P9 Strengthen P95 4. Equivalent proportions You will learn to: Convert between fractions, decimals and percentages Compare fractions, decimals and percentages Write a fraction as a decimal. Extend P99 Test P0 CONFIDENCE Why learn this? Information about proportions can be given as fractions, decimals or percentages. You need to be able to convert between different types. Fluency What is the decimal equivalent of _ _ Can you write the number π as a fraction? Warm up Exercise 4. Write as a percentage. a 7 out of 00 b 5 out of 50 c 0.7 d.9 Work out a 4 0 b c Write each decimal as a fraction. a 0.75 b 0. c Write < or > between each pair of decimals. a 0.5 u 0.7 b 0.6 u 0.60 c u Sort these into five sets of equivalent proportions Key point You can write a fraction as a decimal by dividing the numerator by the denominator. _ 4 = 4 = Q5 hint 5% 0% 7% 70% 75% Rewrite fractions so they have denominator 00 to work out the percentage Write each fraction as a decimal and as a percentage. a 0 = 0.u = u% b 0 = 0.u = u% c _ = 0.u = u% d 7 0 = 0.u = u% e 7_ = 0.u = u% f 0 = 0.u = u% Topic links: Measures Q6 hint Use the S D key on your calculator to change the fraction into a decimal.

2 7 Write each fraction as a decimal and as a percentage. a = 0.u = u% b 7 = 0.u = u% 40 _ _ 50 _ 5 c 90 = 0.u = u% d 05 = 0.u = u% e = 0.u = u% f = 0.u = u% Problem-solving Which shape has the longer perimeter? A B m 0 0. m 0. m 7 m 0 0. m 0.4 m m 0 m 0 9 Use the decimal equivalent of each fraction to write the sets in order, smallest to largest. a 0 _ 5 5_ b _ Put these values in order, smallest to largest % 9 out of 6 0 Worked example Write 0.45 as a fraction = = There are decimal places so 45 has been divided by 000 Divide numerator and denominator by 5 to simplify. 49 and 00 don t have any common factors so it cannot be simplified further. Write each decimal as a fraction. Simplify where possible. a 0.5 = 5 = 00 b 0.75 = _ u 000 = c 0.4 d 0.5 e 0. f 0.75 g 0.9 h Write each percentage as a fraction. Simplify where possible. a 5% = 0.5 = u = _ u 00 0 b 6% = u 00 = u u c % d 5% e.5% = 0.5 = _ 5 = 000 f 7.5% g 45.% h.% Can you write π as a fraction? Choose some sensible numbers to help you explore this situation. Then use what you ve learned in this lesson to help you answer the question. 4 Reflect This lesson uses a lot of mathematical terms, such as terminating equivalent percentage common factor. Write down what each of these terms means, in your own words. Which terms are new, and which ones have you met before? Key point A terminating decimal ends after a definite number of digits, for example 0.9 and.04. You can write any terminating decimal as a fraction. Q hint Use the number of decimal places to decide whether the denominator should be 00 or 000. Reflect Pi, Section 4. Unit 4 Fractions, decimals and percentages 0

3 Master Check P9 Strengthen P95 Extend P99 Test P0 4. Recurring decimals You will learn to: Write recurring decimals as fractions. CONFIDENCE Why learn this? Lots of calculations in real life have an answer that is a recurring decimal. Fluency Round each number to decimal places How can you tell if a fraction will be a terminating or a non-terminating decimal? Warm up Exercise 4. Work out a 76 6 b 75 5 c 45 4 d 4 a i Jarred thinks of a number. Half of it is 40. What is _ 4 of his number? ii What number did Jarred think of? b i Sophie thinks of a number. _ 6 of it is. What is _ of her number? ii What number did Sophie think of? c i Amee thinks of a number. 0 of it is 50. What is _ 5 of her number? ii What number did Amee think of? Reasoning a Use your calculator to match each fraction to its equivalent decimal b Use the decimals to order the fractions in part a, smallest to largest. Worked example Write _ 9 as a decimal. 9) 0 9 doesn t go into so write a 0 in the units column There are now 0 tenths. 0. 9) = goes into 0 once with remainder. There are now 0 hundredths. Continue like this and the decimal recurs. Qb hint 6 6 Key point A recurring decimal contains a digit, or sequence of digits, which repeats itself forever. A dot over the digit shows it recurs. For example, 0.. = 0. 4 Write each fraction as a decimal. a _ b c 5 d 7_ e _ 6 f 5_ 6 g _ 9 h _ 9

4 5 Problem-solving / Reasoning Nira works out and gets an answer of on her calculator. What is the equivalent fraction? Discussion What has the calculator done? 6 Use a written method to work out each division. Write your answers as recurring decimals using dot notation. a b 75 9 c d 65 9 e 97 f 756 Investigation Reasoning / Problem-solving Caroline says, Some fractions can be written as terminating decimals but some are recurring decimals. Write each fraction as a decimal. _ _ _ 4 _ 5 _ 6 _ 7 _ _ 9 0 Sort them into terminating decimals and recurring decimals. Jack says, If the denominator of a fraction is even, it will be a recurring decimal. Find an example to show that Jack is wrong. 4 Which denominators give terminating decimals? Discussion Caroline says, I think it s to do with the fact that 5 = 0. What do you think she means? 5 Investigate what happens if the numerator is not. 7 a Which bag has the greater proportion of red counters? b What is the proportion of blue counters in each bag? A B The pie chart shows the first language of people working in a summer school. Write the proportion of each language as a fraction and as a percentage. International School Languages Chinese English French Russian Q hint How many degrees represent the whole pie chart? 9 How can you tell if a fraction will be a terminating or a non terminating decimal? Is it easier to explore this question now you have completed the lesson? What further information do you need to be able to answer this? 0 Reflect A shorthand way of writing a recurring decimal is to use a dot, or dots, over the numbers that repeat. For example, 0. is written as 0. Write down five other short forms that you use in maths. Do you think these short forms are useful or not? Reflect Pi, Section 4. Unit 4 Fractions, decimals and percentages

5 Master Check P9 Strengthen P95 Extend P99 Test P0 4. Adding and subtracting fractions You will learn to: Add and subtract fractions Add and subtract mixed numbers. CONFIDENCE Why learn this? Statisticians add and subtract fractions to work out the probably of different events happening (or not happening). Fluency What is _ + _ 4 _ _ 4 _ 5 _ + _ 0 How many years ago did people start writing fractions? Exercise 4. Warm up Write each improper fraction as a mixed number. a 4 5 b 0 c 7 d Write each mixed number as an improper fraction. a _ 4 b _ c 5 _ c 4 Work out a 5 + _ b 5_ 6 _ c _ 4 _ d _ + _ Work out each calculation. Give your answer as a mixed number where necessary. a 5_ + _ + _ b c 5_ 9 _ 9 + 7_ 9 d _ _ + _ 4 e 4_ _ 4 f _ 4_ 9 + _ 6 5 Work out a _ + _ + _ 4 b _ + _ 4 + _ 5 c _ 4 + _ 5 + _ 6 6 Problem-solving Work out the missing number. a 4_ 5 + _ 4 + u = b 5_ 6 + _ 5 u = Q4a hint Problem-solving In a clothes shop, _ 5 of clothes are suits, _ are trousers and the rest are tops. What fraction of the clothes are tops? Worked example a Work out 5_ 6 + _ 4 5_ 6 + _ 4 = ( + ) + ( 5_ 6 + _ 4 ) = 4 + ( ) = = = 5 7 Add the whole number parts and add the fraction parts separately. Convert the fractions to equivalent fractions with a common denominator. Change the improper fraction to a mixed number so you can add the whole number parts.

6 b Work out _ 5_ 6 _ 5_ 6 = ( ) + ( _ 5_ 6 ) = + ( _ 6 5_ 6 ) = + ( _ 6 ) = _ = _ Subtract the whole number parts and the fraction parts separately. Work out a _ b _ 4 + _ 5 c _ + _ 5 d 4_ 5 + _ e 4 _ + 5_ 6 f _ 5 g + 5_ 6 h _ 4 + 4_ 5 i 5_ 9 + 5_ 6 9 Work out a 7 0 _ 5 b _ 4 _ c 4 5_ 6 _ d 4_ 5 _ e 4 _ _ 6 f 7 0 _ 5 g 4 5_ 6 h _ 4 _ 5 i 5_ 6 5_ 9 0 Yazdi uses _ 4 litres of white paint and _ 5 litres of blue paint. How many litres of paint did he use in total? Give your answer as a mixed number. Peter walked 4 5_ 6 km, Brenda walked 4_ 5 km. How much further did Peter walk? A farmer needs _ 5 metres of netting for his chickens. He already has metres. How much more does he need? 0 A box of apples weighs 5_ 7 kg and a box of pears weighs _ 5 kg. How much do they weigh altogether? Investigation Write down six fractions that are between a 0 and b 0 and _ c _ and Reasoning 0 Write down two fractions that are between a _ 4 and _ 4 b _ and _ c 7 0 and 0 d _ 5 and 4_ 5 Discussion In how many different ways can you answer the questions in this investigation? 4 How many years ago did people start writing fractions? What information do you need to start answering this question? 5 Reflect Choose one of the parts of Q9 that you felt confident in answering. How would you explain the method you used to a classmate who had missed this lesson? Reflect Pi, Section 4. Unit 4 Fractions, decimals and percentages 4

7 Master Check P9 Strengthen P95 Extend P99 Test P0 4.4 Multiplying fractions You will learn to: Use strategies for multiplying fractions. CONFIDENCE Why learn this You multiply fractions when working out the distance you can travel with half a tank of fuel. Fluency What is _ 7 of _ 5 of 5 _ 9 of 6 5_ 6 of 7 How many times can you cut a piece of paper in half? Warm up 5 Exercise 4.4 Work out a _ 4 b _ 7 c _ 5 d 4 _ 9 e 5_ 6 4 f _ 6 Write each improper fraction as a mixed number in its simplest form. a 0 b 4 c 5 5 d 4 6 What is the inverse operation of a multiplying by 0 b dividing by? 4 Simone says, I m thinking of a number. I multiply it by and then divide the answer by, and get 5. What number was she thinking of? 5 Reasoning Work out a 4 b _ 4 c 4 d Explain why the answer is the same in parts a, b and c. 6 Work out a 6 _ b 5 4_ 5 c _ d 5_ Work out a _ 5 50 b _ 60 c _ of 60 Real / Problem-solving A car has 45 litres of fuel in the tank. The driver uses _ 5 of the fuel. How many litres of fuel are left? 9 Reasoning Which of these products will have an answer less than? a 5 _ b _ 9 7 c 4 5 d _ 4 6 Q Literacy hint An inverse operation is the opposite operation. Q6b hint Work out one-fifth of 5, then multiply it by 4. Q7a hint Work out one-fifth of 50, then multiply by.

8 Worked example Work out _ 4 _ _ 4 _ = 4 = = _ 6 4 of _ 4 of _ = _ 6 Key point To multiply two fractions, multiply their numerators and multiply their denominators. 0 Work out each calculation. Simplify your answer where needed. a _ _ 4 = 4 = u u = u u b _ 4 4_ 5 c _ _ 5 d _ 4 _ 4 e _ 4 6 f 4_ 9 _ 7 g _ 5 7 Work out a _ _ 4 b _ _ c _ _ 5 d _ _ Discussion What happens to the denominator when you multiply a fraction by _? Work out a ( _ 4 ) = _ 4 _ 4 = b ( _ ) c ( _ 5 ) d ( _ 6 ) e ( _ ) f ( _ ) Worked example Work out _ _ 9 _ _ 9 = _ 9 = _ 9 = _ _ 9 = _ 4 _ = Rewrite the calculation with a fraction that can be simplified. is a factor of and is a factor of 9. Simplify the fractions before multiplying. Key point Sometimes you can rearrange fractions so they can be simplified before multiplying. Discussion How could you work out the multiplication using fewer steps? Work out a 5_ _ 5 b _ 4 _ 7 c _ 4 d 4_ 9 _ e 9 5 5_ 6 c 5_ Holly drank _ of a _ litre bottle of juice. How much did she drink? 5 How many times can you cut a piece of paper in half? Choose some sensible numbers to help you explore this situation. Then use what you ve learned in this lesson to help you answer the question. 6 Reflect Look again at Q. Write down the steps you took to work out the answer. Work out the answer again using a different method. Did you get the same answer? If not, check your working. Reflect Pi, Section 4.4 Unit 4 Fractions, decimals and percentages 6

9 Master Check P9 Strengthen P95 Extend P99 Test P0 4.5 Dividing fractions You will learn to: Divide by fractions. CONFIDENCE Why learn this Real-life measurements are not usually whole numbers. You need to be able to calculate with fractions too. Fluency How many s are in 4s are in 0 s are in 5s are in 00? Does division always make something smaller? Warm up Exercise 4.5 Write down the common factors of each pair of numbers. a 0 and 5 b 6 and 40 c 7 and 6 d 5 and 55 Work out a _ 4 b _ 0 c 4_ 5 _ d 9 0 _ Write each improper fraction as a mixed number. a _ b 5 6 c 4 Complete these calculations for each diagram. a = u u = 4 4 u = b c 6 = _ u = u u u = u u = u u = u u u = u 5 Use your answers to Q4 to work out a how many quarters are in b how many thirds are in c how many halves are in d how many quarters are in. 6 Copy and complete. a 4 _ b _ 5 c _ 6 d 6 _ 4 7 How many _ 4 litre bottles can be filled from a litre container? Katie cuts 4 chocolate cakes into eighths. How many slices are there? 9 Reasoning Chris cuts carrot cakes into equal slices. He has 0 slices. What fraction did he cut each cake into? Q6a hint How many halves are in 4? 7

10 0 Write the reciprocal of each fraction or number. a _ = u b _ 4 c 4 d 5 e f 4 g _ h Worked example Work out 5 _ 0 Q0 Literacy hint The reciprocal of a fraction is the upside down fraction. Q0e hint The number can be written as _. 5 _ = 5_ _ = 5 = 7 _ Multiply by the reciprocal of _. 5 = 5_. Write as a mixed number in its simplest form. Key point Dividing by a fraction is the same as multiplying by its reciprocal. The reciprocal of a fraction is the upside down fraction. Work out a 6 _ b 4 _ 4 c 0 5_ 9 d e _ 9 f 7 0 g 5 _ h 6 5 How many _ 4 kg bags of potatoes can be filled from a kg sack? STEM An electrician needs to cut a 0 m roll of cable into lengths 5_ 6 of a metre. How many lengths can she cut from the roll? 4 Decide if these statements are true or false. Give examples to help explain your answers. a The reciprocal of a proper fraction is another proper fraction. b The reciprocal of an improper fraction is a proper fraction. c When you multiply two fractions the answer is always less than. d When you multiply two proper fractions the answer is always less than. e When you multiply an integer by a proper fraction the answer is more than that integer. f When you divide an integer by a proper fraction the answer is greater than the integer. 0 5 Does division always make something smaller? Choose some sensible numbers to help you explore this situation. Then use what you ve learned in this lesson to help you answer the question. 6 Reflect Fraction calculations can often be shown using bar models as in Q4. Do these diagrams help you understand how to divide by fractions? Explain. Reflect Pi, Section 4.5 Unit 4 Fractions, decimals and percentages

11 Master Check P9 Strengthen P95 Extend P99 Test P0 4.6 Comparing proportions You will learn to: Use a calculator to work out percentages Compare proportions. CONFIDENCE Why learn this? Nutritional information on food packets can be given as a fraction, a percentage or as a decimal. Fluency Work out 0% and 5% of How do calculators show 50%? Exercise 4.6 Work out a 5% of 00 b 5% of 00 c 0% of 00 d 75% of 00 Write these scores in order, from lowest to highest. 6 out of 0 out of 0 4 out of 5 9 out of 50 Warm up Write down 6 sets of equivalent fractions, decimals and percentages from these % % % % %..% 4 Write these amounts in order, from smallest to largest. a _ 9 4% out of 0 b % 4 out of 50 _ 5 Reasoning Which is better value? a _ off or a discount of 0% b A reduction of 5% or a saving of c 0% off or pay 4_ 5 of the cost 6 Problem-solving A swimming team has 0 members. members are girls. What percentage of the swimming team are boys? 0 9 Topic links: Statistics, Proportion, Pie charts Subject links: Cookery (Q7), Geography (Q)

12 7 Reasoning / Problem-solving Here is some Brand A nutritional information for two similar products. Per 00 g a Write the proportion of fat in Brand A as Protein a percentage Carbohydrate b Which brand has a higher proportion of fat? Fat c Write the proportion of protein in Brand A as a percentage. d Which brand has a higher proportion of protein? e Which brand has a higher proportion of carbohydrate? Problem-solving The ratio of boys to girls in a class is : 4. What percentage of the class are girls? 9 Problem-solving / Reasoning This pie chart shows the languages studied by students at a school. Languages being studied 50 0 Spanish French German.5 g g 4.5 g Brand B Percentage content Protein 5% Carbohydrate.5% Fat 5% Q9 Strategy hint Use the pie chart to work out the fraction of students who study French. a 5 people study French. How many people were surveyed? b How many people study i German ii Spanish? 0 Problem-solving / Reasoning Dave s driving theory test had 0 questions in it. He scored 70%. How many questions did he get wrong? Problem-solving / Reasoning 0 students voted in a school council election. 56 people voted for Matt, the rest voted for Hassan. What percentage of votes did Hassan win, to the nearest %? Max scored 00 out of a possible 50 in his maths test. What was his score as a percentage? Real There are 50 states in the USA. 7 of them have no coast. What percentage of the states have no coast? 4 How do calculators show 50%? Look back at the maths you have learned in this lesson. How can you use it to answer this question? 5 Reflect Q0 and Q are tagged as problem-solving questions. This means that there are alternative ways of finding the answer. Which method or methods did you choose? Explain why. Q hint 00 out of 50 = _ = Reflect Pi, Section 4.6 Unit 4 Fractions, decimals and percentages 90

13 Master Check P9 Strengthen P95 Extend P99 Test P0 4.7 FINANCE: Percentage change You will learn to: Work out a percentage increase or decrease. CONFIDENCE Why learn this? Understanding percentage change means you can make sure you don t get overcharged or short-changed. Fluency Write as a percentage of What does Up to 00% less sugar actually mean? Warm up 9 Exercise 4.7: Percentage change Work out 0% of a 70 b 5 c 0 d 44 e 90 Write each improper fraction as i a mixed number ii a decimal iii a percentage. a _ b _ c d 5 _ Increase each amount by 0%. a 60 0% = 0% = 60 + = b 400 0% = 0% = = c Work out a 0 increased by 0% b $600 increased by 5% c 500 increased by 0% d 400 increased by 5% e $500 increased by 5% f 450 increased by 50% 5 Decrease each amount by 5%. a 40 4 = u 5% of 40 = u 40 u = u b 00 c Key point An increase of 0% means original amount (00%) + 0% of that amount = 0% of the amount. Q5a hint 5% = _ 4 so divide by 4.

14 6 Work out a 0 decreased by 5% b $00 decreased by 0% c 60 decreased by 0% d 90 decreased by % e 050 decreased by 5% f $400 decreased by 0% FINANCE 7 Finance A travel company advertises these holidays in June. Albania 650 Bulgaria 75 Croatia 56 All the prices go up by % in July. How much is each holiday in July? Real / Finance a A newspaper headline reads, House prices rise by 00% in the last decade. What does that mean? b May s house has increased in value by 00% since she bought it. It cost her How much is it worth now? Q hint An increase of 00% means add on 00%. 9 Finance a A coat costs 0. It is reduced by 0% in a sale. What is its sale price? b A pair of jeans cost 70. They are reduced by 45% in a sale. What is the sale price? 0 Finance Work out the cost of each item when 0% VAT is added. a A computer that costs 70 b A meal that costs 55 c A haircut that costs Finance / Problem-solving Janet needs a new sofa. Which shop has the cheaper price? Shop A Sofa: 50 0% off! Shop B Sofa: 40 5% off! Q0 Literacy hint VAT (Value Added Tax) is a tax that is added to some goods and services before you buy them. Reasoning Eli saves 0, which is 0% of his allowance. How much is his allowance? Finance A savings account advertises: Earn % on your investment each year Q hint The interest is only paid on the original investment. Sue invests 000. a How much interest will Sue receive each year? b Sue doesn t put any more money into the account. How much money will Sue have in the account in total after 5 years? 4 Reasoning Jamie s savings account pays 5% interest each year. He receives 0 after year. How much money was in the account? 5 What does Up to 00% less sugar actually mean? Look back at the maths you have learned in this lesson. How can you use it to answer this question? 6 Reflect In this lesson some questions are about interest. Explain in your own words what is meant by interest and why it might be useful to understand its meaning. Q4 hint 0 is 5% How much is 0%? How much is 00%? Reflect Pi, Section 4.7 Unit 4 Fractions, decimals and percentages 9

15 Master P79 Check Strengthen P95 Extend P99 Test P0 4 Check up Log how you did on your Student Progression Chart. Equivalent proportions Copy and complete the table showing equivalent fractions, decimals and percentages. Write fractions in their simplest form. Fraction Decimal Percentage % _ 0. Write 0. as a fraction in its simplest form. Write each fraction as a decimal. a _ b _ 9 4 Write < or > between each pair of fractions. a 9 5 u 5 b _ u Write these values in order, smallest to largest % out of 5 0 Fraction calculations 6 Work out a 5_ 9 + _ 6 b 9 0 _ 4 7 Work out the sum of _ 4, 5_ 6, and _. Write your answer as a mixed number. Work out each calculation. Write your answers in their simplest form. a _ 4 _ 5 b _ 9 _ 7 c ( _ 5 ) 9 Work out a 4 _ b _ 4 + _ 5 c 9 0 4_ 5 d _ 0 Chantel needs 5 lengths of ribbon. Each length is _ 4 metres. She says, I know I will need less than 5 metres altogether. How does she know? Work out 6 _ Work out a 7 _ b 4 _ 5 c _ Write the reciprocal of a 6_ 7 b 7 c _ 0 9

16 Percentages 4 The ratio of boys to girls in a class is 9 :. What percentage of the class are boys? 5 A football club has 0 male players and 5 female players. What percentage of the club are a male b female? 6 Work out a 460 increased by 5% b $4500 increased by 5%. 7 Anna has to pay 0% tax on a laptop. The laptop costs 450 before tax. How much does Anna pay in total? Brian invests 5000 with yearly interest paid at %. How much interest will he earn after year? 9 A flat increased in value by 50%. It was worth What is its new value? 0 Work out a 0 reduced by 5% b 00 reduced by 5% Steve s car has gone down in value by 5%. He paid 600. What is it worth now? 0% of an amount is $5. What is the amount? How sure are you of your answers? Were you mostly Just guessing Feeling doubtful Confident What next? Use your results to decide whether to strengthen or extend your learning. Reflect Challenge 4 Jarred draws a square. He colours in half red. He colours in half of the rest orange. He continues like this, colouring in half of what s left using the colours of the rainbow: red, orange, yellow, green, blue, indigo, violet. a What fraction of the square will be coloured indigo? b What fraction will be coloured violet? c Freya tries a similar experiment, colouring in _ of the shape each time. the different fractions in Freya s shape. Unit 4 Fractions, decimals and percentages 94

17 Master P79 Check P9 4 Strengthen You will: Strengthen your understanding with practice. STRENGTHEN Extend P99 Test P0 Equivalent proportions Write each of these as a decimal number. a 4 00 b 7 00 c 00 d 9 00 e 5% f 65% Write each decimal as a i percentage ii fraction in its simplest form. a 0. b 0. c 0.6 Write each fraction as a percentage. a _ 4 b 50 c 7 0 d 7 0 e 9 4 Match up equivalent fractions, decimals and percentages..4 0% 4 40% Qe hint 5% is the same as 5 out of 00 = 5 00 Qb hint 0. = _ 00 Simplify the fraction. Q hint Write an equivalent fraction with denominator 00. 5%.5 0% Write each decimal as a fraction. Simplify where possible. a 0. = _ u b 0.76 c 0.44 d 0.5 e 0.9 f 0.75 g 0. 6 Rewrite each recurring decimal using dot notation. a b. c.5 55 d Write these decimals in order, from smallest to largest. a b c d Use a written method to work out each division. a 5 5 b 5 9 c 56 9 Use a written method to write each fraction as a decimal. a 7_ b _ c 5 6 d 6 Q6 Literacy hint A dot above a digit shows it recurs = A dot above the beginning and end of a sequence shows the whole sequence recurs = Q7a hint Which is larger: 0. or 0..? Qa hint _ 5) 5 Q9a hint 7. ) 0.uuu

18 0 Which of these fractions will give a recurring decimal? Write < or > between each pair of fractions. a _ u 0 b _ u 5 _ c 4_ u 7 5_ 9 d _ 9 u 9 Q hint Write each fraction as a decimal. Match each proportion to a bar. Use them to write the proportions in order, from smallest to largest. A 0.7 B 0.5 C 60% D _ E _ 4 i ii iii iv v Write these proportions in ascending order. a 4_ % 0.6 _ b 95% 5_ _ Q Literacy hint Ascending means getting larger. Fraction calculations Write each improper fraction as a mixed number. a b 5 c 5 4 d 4 9 Write each mixed number as an improper fraction. a 4_ 5 b _ 4 c _ 9 d 4_ 7 Work out each calculation. Write your answer as a mixed number. a _ + 5_ + 7_ = u = u b 4_ 9 + 7_ 9 + _ 9 c 4_ 5 + _ 5 + _ 5 d Work out the missing number. a 5_ 9 + _ 9 + u = b _ 9 4_ 9 = u c u = d _ 7 _ 7 = u e _ u = f 7 + _ 6 + u = g _ 5 0 = u h 5_ _ 4 = u Qa hint Qa hint = = u _ 5 Q4a hint How many ninths equal? Unit 4 Fractions, decimals and percentages 96

19 5 Problem-solving What fraction should the third sector on this pie chart be labelled? Q5 Strategy hint Write the question as a subtraction calculation. 6 Work out a _ + 4_ 5 = + + _ + 4_ 5 = u + u u c 4_ 5 _ 4 = ( ) + ( 4_ 5 _ 4 ) = u + u u 7 Work out a _ of _ = = u u c _ _ 7 b 4 5_ 6 + _ 5 d 5 _ _ 4 b _ 4 of 4_ 5 d _ 4 _ 4 Work out a _ 4 5_ 9 b _ 5 _ c 5_ 9 _ 5 9 Work out a _ 4 = _ 4_ = u c 6 _ d 6 _ 5 b _ 4 = _ 4_ = u Q7a hint Finding a fraction of an amount is the same as multiplying by the fraction. of Q9a hint How many quarters in? Percentages The price of a computer has increased by 5%. It was originally 450. What is the new price? Reasoning Frankie works out 50 reduced by 0% like this: x 0% of 50 = 5 0% of 50 = 46 x Q hint 0% of 450 = u 5% of 450 = u 5% of 450 = u + u = u u = u Q hint 00% 0% = 0% Rob works it out like this: 0% of 50 = 5 0% of 50 = = 46 Whose method do you prefer? Why? The value of a car has gone down by 5%. It was originally worth 000. What is the new value? 97

20 4 A holiday costs 00. Booking before the end of the month saves 5%. How much is the holiday with the saving? 5 Reasoning / Problem-solving a 0% of a number is 5. What is the number? b 5% of a number is 50. What is the number? c 0% of a number is 4. What is the number? d 40% of a number is 0. What is the number? Q5c Strategy hint 0% = % = u % = u Enrichment Draw a pie chart to show how you spent the 4 hours in a weekday during term-time. What fraction or percentage of your time is spent a sleeping b in lessons c eating/washing/getting ready d socialising/entertainment/tv e homework? Q hint Number of degrees for each hour = 60 4 hours. How would your pie chart from Q be different for a Saturday in school holidays? Reflect List these tasks in order from easiest to hardest. A Adding and subtracting fractions B Multiplying fractions C Dividing fractions D Adding and subtracting mixed numbers E Multiplying mixed numbers F Dividing mixed numbers Look at the first task in your list (easiest). What made it easiest? Look at the two tasks at the bottom of your list (hardest). What made them hardest? Write a hint to help you with the two tasks you found hardest. Q hint List the letters of the tasks in order. You don t need to write out the descriptions. Reflect Unit 4 Fractions, decimals and percentages 9

21 Master P79 4 Extend Check P9 Strengthen P95 You will: Extend your understanding with problem-solving. EXTEND Test P0 Write each percentage as a decimal. a.5% b 5.% c 5.4% d.9% e 4.75% f.5% Write each decimal as a percentage. a 0.5 b 0.59 c d 0.4 e f Write each terminating decimal as a fraction in the simplest form. a 0. b 0.99 c 0.75 d 0.05 e.65 f 4.4 g.05 h Work out the first amount as a percentage of the second amount. a 0p out of b 750 ml out of litres c 40 minutes out of hours d 50 cm out of 4 metres e.5 kg out of 5 kg f.4 km out of 6 km Q4 hint Make sure the units are the same. 5 9 out of 0 members of a tennis club are male. a What fraction of the club are female? b What percentage of the club are male, to the nearest %? 6 Real 0 out of 96 countries in the world have Spanish as their official language. What percentage of countries is that, to the nearest %? 7 Reasoning Sort these fractions into terminating or non-terminating decimals. _ _ _ 4 _ 5 _ 6 _ 7 _ _ 9 0 Write these fractions in order from largest to smallest. a _ _ _ 5 b _ Reasoning Write each fraction as a decimal to show why each statement is true. a _ > 0 b _ > _ 5 c 4_ 9 < _ d _ 4 < 7_ 9 0 Write each time as a mixed number. _ a hour 45 minutes = u u hours c 5 hours 40 minutes e hours 55 minutes g hour 5 minutes i 5 minutes b hour 0 minutes d hours 5 minutes f hours 5 minutes h 0 minutes j 50 minutes Q7 Strategy hint Use division if you are not sure. Q Strategy hint Write each fraction as a decimal to compare them. Q0a hint 45 minutes = of an hour Simplify the fraction. Write each of the times in Q0 as a decimal number of hours. 99

22 Work out each calculation. Give your answer in hours and minutes. a hours 0 minutes 5 = u hours 5 = _ hours _ minutes u b 4 hour 45 minutes c hours 0 minutes Modelling / Problem-solving A film lasts hours 5 minutes. A cinema plays it continuously from :00 to :00. How many times is it played? 4 A bus journey to the city lasts hour 5 minutes each way. Raghev travels by bus into the city and back three times a week. What is the total time Raghev spends travelling by bus to the city each week? 5 Match pairs of times. A hour 6 minutes B hours minutes C hours 54 minutes D hour minutes E hours 4 minutes F hour minutes i.9 hours ii.5 hours iii. hours iv. hours v.05 hours vi. hours 6 Real 5 million people were recorded in the 0 census for England. Of these, approximately 6 million people were under 0 years old. What percentage were under 0? 7 A restaurant bill costs 00 plus taxes. The final bill including tax is 0. What percentage of the restaurant bill is tax? Work out the percentage increase. The first one has been started for you. a 0 increased to 00 Difference: 00 0 = 0 Difference = _ 0 Original amount 0 = _ = u% 4 Increase of u% Check: 0 + 5% = u b 0 increased to 44 Difference: 44 0 = u c 500 to 650 d 60 to 405 e $40 to $45.60 Q hint Percentage = amount of original change increase amount 9 Before tax a bike costs 490. With tax it is What percentage was the tax? 0 A school has increased in size from 00 pupils to 464 pupils. By what percentage has the school size increased? The cost a bag of bananas has risen from.40 to.47. What percentage increase is this? Unit 4 Fractions, decimals and percentages 00

23 Work out the percentage decrease. The first one has been started for you. a 0 decreased to 6 Difference: 0 6 = Difference = _ = 0.5 Original amount 0 = u% Decrease of u% b 0 decreased to 96 Difference: 0 96 = u c 500 to 5 d 60 to 4 e $50 to $.75 Q Strategy hint Check your answer by working out the decrease. Real A ski helmet is reduced from 50 to What percentage is it reduced by? 4 Real A jacket costs 0. There is 5 off. What percentage reduction is this? 5 Work out a _ 5 + _ b 4 5_ 6 _ _ 9 c _ _ 4 5_ 6 d _ 6_ 7 _ 4 e ( _ 4 ) _ f ( _ 4 _ ) g (6 _ ) _ 4 h 6 ( _ _ 4 ) 6 Use division to write each fraction as a decimal. a 7 b 4 5 c 7 7 Write the reciprocals of each number. Give your answers in their simplest form. a 7 b 4 5 c 5_ 6 Work out the sum of _ 9,. and 4 _ 4 Q7c hint Write mixed numbers as improper fractions first. 9 How many _ 4 litres bottles can be filled from a 9-litre container? 0 Problem-solving Graham, Andrea and Carly are playing a missing-number game. Graham says, 5% of my number is 70. Andrea says, 5% of my number 75. Carly says, 0% of my number is 60. What is the sum of all three of their numbers? Investigation Reasoning / Modelling / Problem-solving Write the next four terms in each of these fraction sequences. a _, _, _ 4, _ 5, b _, _, _ 4, 4_ 5, c 9 0, _ 9, 7_, Write each term in the sequence as a decimal number. Bhavika says, Each sequence is getting closer and closer to a number. For each sequence, write down which number it is getting closer to. Discussion Do you think the sequence will reach that number? Explain 0

24 a Match each statement to the percentage it gives of the original amount. A An increase of 0% B A decrease of 0% C Interest of % D Interest gain of % E Saving of 0% F % reduction G % less i 70% ii % iii 0% iv 99% v 90% vi % vii 0% b Write each percentage in part a as a decimal. Work out these percentages of amounts using a decimal multiplier. a 0% of 756 = = u b 5% of 650 = 0.05 u = c 7% of 675 d 90% of 4 e 7% of 40 f 5% of 000 Use a decimal multiplier to work out a 0 increased by 0% b 500 increased by 5% c $400 increased by 5% d 40 increased by.5%. 4 Use a decimal multiplier to work out a 40 decreased by 0% b 500 decreased by 5% c $00 decreased by 0% d $700 decreased by % e 4 decreased by 5% f 50 decreased by 7.5%. 5 Problem-solving / Finance An insurance company offers two ways of paying. Only per month for a year! Key point You can multiply an amount by a decimal multiplier to work out percentage change. Qa hint An increase of 0% = 00% + 0% = 0% = u.u Q4a hint A decrease of 0% = 00% 0% = 90% = u.u ONE-OFF PAYMENT OF 40. a How much more expensive, overall, is the pay monthly option? b What percentage of the yearly payment is added to the monthly option? 6 Reflect Write down three new skills you have learned in this unit. For each one of these, choose a question that used this new skill. Reflect Unit 4 Fractions, decimals and percentages 0

25 Master P79 Check P9 Strengthen P95 Extend P99 TEST 4 Unit test Log how you did on your Student Progression Chart. Write each decimal number as a percentage. a 0.5 b 0. c 0.0 d.4 Write each decimal number as a fraction or mixed number in its simplest form. a 0.0 b.5 Write 0 as a a percentage b a decimal. 4 Write these fractions in order, smallest to largest _ _ Write 4 as a decimal. 5 6 Work out a _ 5 + _ 6 b _ 9 _ 7 Work out 4_ 7 + 5_ 7 + 6_ 7. Give your answer as a mixed number in its simplest form. Work out a 4 4_ 5 0 b _ + 4_ 5 9 In a triathlon, Rich swims _ 4 km, cycles km and runs 4_ 5 km. What is the total distance covered by the triathlon? 0 The ratio of boys to girls in a class is :. a What fraction of the class are girls? b What percentage of the class are girls? Increase $640 by 5%. Work out 4 _ 6 Work out each calculation. Give your answers in their simplest form. a 4 5 _ b _ _ 5 5_ 9 c _ 4 4 Write the reciprocal of a b c 0 d 5 A house increased in value by 00%. It was originally worth What is its new value? 5 0

26 6 Reduce 470 by 6%. 7 A restaurant bill says % service charge. How much is the total bill, with service charge? 5% of a number is 4. What is the number? 9 A truck has gone down in value from to By what percentage has the value reduced? 0 Write hours 5 minutes as a a fraction of an hour b a decimal proportion of an hour. Copy and complete, writing < or >. 4_ 5 u 7_ 9. Write the decimal multiplier for working out a a 90% increase b % increase c 40% decrease d % decrease Challenge Reasoning Use these number cards to make different proper fractions, for example _ 5 and _. 5 a Work out the sum of your two fractions b Work out the difference between your two fractions. c Do you think the sum is as large as possible? If not, make two different fractions using the numbers. d Do you think the difference is as small as possible? If not, make two different fractions using the numbers. e How can you make sure the sum is as large as possible? f How can you make sure the difference is as small as possible? g Try with 4 different numbers. 4 Reflect Look back at this test. Which questions took the shortest time to answer and which took the longest? Why do you think you could answer some questions more quickly than others? Reflect Unit 4 Fractions, decimals and percentages 04