By using a spreadsheet, if a grade were to change the spreadsheet would automatically recalculate the average.

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1 Spreadsheet What is a spreadsheet? A spreadsheet is simply data organized in rows and columns. Accountants used paper ledgers which were organized in rows and columns to keep track of business activities. These large ledgers spread out to form a "spreadsheet". Accounting spreadsheets kept track of the flow of money, but spreadsheets can be used to organize any type of numeric data. Example: Sports Statistics or Students Marks. A spreadsheet is a record keeping tool that works with numbers. I keep track of student's term marks by using a spreadsheet. The spreadsheet will calculate all the students Term Averages. By using formulas to do calculations, spreadsheets will save you time. In the spreadsheet below, the Average of each student is calculated by the spreadsheet. Example: Name Test 1 Test 2 Test 3 Average Bill Smith Sally Jones John Brown By using a spreadsheet, if a grade were to change the spreadsheet would automatically recalculate the average. The main advantages of using computerized spreadsheets are: 1. The ability to perform calculations on the data. 2. Spreadsheets automatically redo calculations when changes are made to data. Data in spreadsheets is organized in columns and rows. Columns are referenced by letters, (A,B,C,...,Z,AA,...,AN.). Rows are referenced by numbers. ( ). The size of a spreadsheet will be determined by the RAM of the computer you use. Some computers may not be able to store a spreadsheet as large as the maximum allows. Columns are vertical with the letters running across the top. Rows are horizontal with the numbers running down the left side. The intersection of a row and column is called a cell. Cells are referenced by its column letter and row number, called a cell name. Example A1, B12, AA53. Each cell can store a single item of data.

2 The heavy border which surrounds a cell is called the cell cursor. When a cell is surrounded by the cell cursor it is called the selected or active cell. Data can be entered into the selected cell. The cell indicator displays the address of the selected cell. Formulas As mentioned above, the real power of spreadsheets is its ability to perform calculations. Calculations can be done by creating Formulas or by using built in Functions. By using cell references in formulas, the value of a cell can be dependant on the values of the cells used in the formula. Every formula in ClarisWorks must begin with an equal sign (=). Example A B C D =A1+B1+C1 2 3 The value of the cell D1 will be 60. It is determined by the values of the cells A1, B1 and C1. Mathematical operators The following operators are available when writing formulas. Addition + Subtraction - Multiplication * Division / Exponents ^ example: =4^2 value would be 16 Order of operations Works spreadsheets calculate formulas following the mathematical rules of order of operations. What is the value of the following formula =9+12/3 Is it 7 or 13? Works will display the answer 13. Division is performed first followed by addition second. Works evaluates formulas from left to right based on the operation priority. If a formula has two operators of equal priority the leftmost operator is evaluated first. Rules for Order of Operations: 1. Exponents =4+3^2 produces the value Multiplication and Division =3+5*6/2 produces the value 18

3 3. Addition and Subtraction =7+4*2 produces the value 15 To change the order of operations use parenthesis to have Works perform operations of lower priority first. Example: =(7+4)*2 produces the value 22 not 15. Incorrect formulas produce the letters ERR in the cell. This means that an error has occurred in the calculation. Division by zero will produce an ERR. Cell Names in Formulas A cell name may be used in a formula. Works uses the cell name to locate the value needed in the calculation. If the cell is empty or has a label 0 is used for the value. Examples: =B2+C2+D2 =A1*A2 Note: A formula cannot reference the cell it is stored in. The formula stored in cell B2 cannot have B2 in the formula. Functions Works has built in functions to perform common calculations. A function performs a set of calculations and then returns a single value. Functions can save you time and reduces errors when used properly. The functions we will use from Works are: SUM, AVG, COUNT, MAX, MIN Example: Instead of using the formula =B1+C1+D1+E1+F1+G1 Use the SUM function =sum(b1:g1) Function Syntax: =function name(cell references) Functions can be applied to a list of cells or a range of cells. The cells must be placed inside parenthesis immediately following the function name. Example: =sum(a1,c12,b3) - will sum the cells a1, c12 and b3 =sum(a1..a45) - will sum the cells from a1 to a45 Functions can be placed within other formulas. Example: =sum(a1:h1)-b12 - will subtract the value in cell b12 from the sum of the range of cells from a1 to h1 Relative Copying When the same formula will be used many times in the same spreadsheet it is not necessary to retype it every time. This takes time and increases the chance of error. It is possible to copy cell contents or formulas within cells using the COPY-PASTE technique or FILL RIGHT, FILL DOWN or FILL SERIES features. A B C D E

4 1 Name Test 1 Test 2 Test 3 Average 2 Bill Smith =avg(b2:d2) 3 Sally Jones John Brown In the spreadsheet above we have typed the formula in cell E2 which will calculate the average for Bill Smith. The same formula needs to be used for Sally and John. The only difference in the formula will be the cells which the avg function will be applied on. When using COPY&PASTE or FILL DOWN to copy the formula to the appropriate cells, Works will change row and/or column references relative to were the formula is copied. That means when the formula in E2 is copied to E3 Works will change the row references by one. Cell E3 will have the formula =avg(b3:d3). If the formula is copied from E2 is copied to E4 Works will change the row references by two. Cell E4 will have the formula =avg(b4:d4). Absolute Copying Sometimes when copying formulas you do not want Works to change the row or column references of certain cells. By using absolute cell referencing Works will allow these cells to remain constant when the formula is copied. A B C 1 Name Test 1 Percent Bill Smith 25 =b3/$b$2*100 4 Sally Jones 34 5 John Brown 19 In the spreadsheet above we have entered a formula in cell D3 which calculates the percentage Bill Smith got on a test marked out of 35. If we did not use an absolute reference for C2 the formula would copy to D4 as =c4/c3*100. This formula would produce the wrong percent for Sally Jones. By using a $ sign in front of the column and row reference, cell c2 becomes an absolute reference and will remain constant when the formula is copied. Copying from D3 to D4 would produce the correct formula of =c4/$c$2*100. Note: To create an absolute reference hit the F4 key immediately after entering the cell reference in a formula. Charts and Graphs Numeric data may be difficult to interpret. It is has been shown that people understand and remember more about information when it is presented graphically. This is why it is sometimes better to display data in the form of a chart or graph. Charts show the relationship between

5 different pieces of data better than columns of numbers. Works has two types of charts: Series charts and Pie charts. Series charts include line, bar and stacked bar charts. Series charts are used to show changes in data over time or in different categories. Pie charts are used to show the relation between the fractional parts that make up a whole amount. Each slice of a pie represents a part of the whole. The size of the slice is determined by its percentage of the whole. Line Charts: Bar Charts: Pie Charts: changes over time changes in different categories compare parts to a whole amount Parts of Charts Series - can have up to 6 series of numbers in one bar or line chart but only 1 series of numbers in a pie chart. Each series should have the same amount of numbers. The series is the data you are charting. X-axis - The horizontal axis on bar and line charts. Can have a title and labels describing the data. Y-axis - The vertical axis on bar and line charts. Can have a title and a scale which shows the numeric value of the charted data. Data Labels - The text which describes each number in a series. The labels can appear above the data or on the X-axis. You will have a label for each number in the series you have charted. Legend - The text which describes each series of numbers in your chart. If you have 3 series in your chart you will have 3 legend items. Pie charts do not allow legends as there is only 1 series represented. Title - Charts can have a Title and Sub-Title to describe the chart. Bar and Line charts can also have titles on the X-axis, Y-axis and the right vertical axis to describe components. these