DECIMALS. Rounding Decimals Review and Multiplying Decimals. copyright amberpasillas2010. Rounding Review. Decimals are read as and

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1 DECIMALS Rounding Decimals Review and Rounding Review Decimals are read as and , Thousands Hundreds Tens Ones Tenths Hundredths Read as 518 and 21 hundredths Thousandths Ten Thousandths 1

2 Rounding Review Find the number. Circle it. Look next door. 4 or less just ignore. 5 or more add one more. Example: Round 5368 to nearest hundreds. Circle the 3 in the hundreds place. Look next door at the 6. It is 5 or more so add 1 more to the hundreds place rounds to 5400 Rounding Review Round to the nearest tenths Round to the nearest hundredths

3 Rounding Review Round to the nearest tenths Round to the nearest hundredths Steps for Step 1: Step 2: Write the problem vertically. Ignore the decimal point(s) and multiply. Step 3: Determine where the decimal point goes in the product. Place the decimal point in the answer by counting how many places the decimal point has moved. 3

4 Multiply 3 x x Multiply 3 x 0.14 Step 1: Write the problem vertically x 3 Step 2: Ignore the decimal points 0 42 and multiply 0.42 Step 3: Determine where the decimal point goes in the product. The decimal moves two places to the left 4

5 Multiply 5 x x Multiply 5 x 0.18 Step 1: Write the problem vertically x 5 Step 2: Ignore the decimal points 0 90 and multiply 0.90 Step 3: Determine where the decimal point goes in the product. The decimal moves two places to the left 5

6 Multiply 0.2 x Multiply 0.2 x x 0.6 6

7 Multiply 0.2 x x Multiply 0.2 x Step 1: Write the problem vertically x Step 2: Ignore the decimal points and multiply Step 3: Determine where the decimal point goes in the product. The decimal moves two places to the left 7

8 Multiply 0.4 x Multiply 0.4 x x 0.7 8

9 Multiply 0.4 x x Multiply 0.4 x 0.7 Step 1: Write the problem vertically Step 2: Ignore the decimal points and multiply Step 3: Determine where the decimal point goes in the product. The decimal moves two places to the left 9

10 200 x Move the decimal two places to the left in your answer. HOW MANY DECIMAL PLACES? 1) 3.1(0.28) 3.1 2) (0.4)(2.53) decimal place decimal places decimal places 1 decimal place 2 decimal places decimal places 10

11 1 1) 0.16 x ) 70 x ) x Evaluate The Power An exponent tells how many times a number is multiplied by itself. Base Exponent 3 is written as This exponent is read three to the fourth power. 11

12 Evaluate The Power Evaluate (0.2) 2 This means (0.2)(0.2) 0.2 x The decimal goes moves two places to the left 0.58 in. Calculate Area With Decimals 4 in. The decimal moves two places to the left. Area base x height Multiply 4 x x in 2 Area is square units! 12

13 THE END!!! Take out your study guide # x Multiply 0.4 x 0.14 Step 1: Write the problem vertically Step 2: Ignore the decimal points and multiply Step 3: Determine where the decimal point goes in the product. The decimal moves 3 places to the left. 13

14 #6 Evaluate The Power Evaluate (0.5) 2 This means (0.5)(0.5) The decimal moves two places to the left x # 7 The Area (A) is the number of square units needed to cover a figure in Area base x height 2 in. The decimal moves two places to the left. Multiply 2 x x in 2 Area is square units! 14