1 Click on the "SLN" tab and enter your name in Cell C1. If Cell C1 is left blank, you will not be able to see your score. 2 Each yellow cell requires a formula. 3 The formula must only contain cell addresses. 4 Each correct formula will begin with =, +, or -. 5 6 The basic mathematical operators are +, -, * and/ 7 Addition: To add the values in cells A1 and B4, the formula is =A1+B4 8 Subtraction: To subtract the value in cell B4 from the value in cell A1, the formula is =A1-B4 9 Multiplication: To multiply the values in cells A1 and B4, the formula is =A1*B4 10 Division: To divide the value in cell A1 by the value in cell B4, the formula is =A1/B4 11 12 Using the SLN function 13 The SLN function has the following syntax: =SLN(COST, SALVAGE,LIFE) 14 Each variable may be either a value or a formula that returns a value. 15 16 Using absolute addresses 18 17 Once a formula is created, you will often want to copy the formula to other columns and rows. It's important to understand that excel always uses "relative addresses" unless you indicate otherwise by creating an "absolute address". For example, if you are calculating the cost of purchasing 2 boxes of cereal at a cost of $3.95 per box, the formula in cell B28 is =B26*B27. Although we read cell B28 as "Multiply 2 boxes by $3.95", Excel is actually calculating the value in cell B28 as "Multiply the value in the cell in the same column (column B) 2 rows above (row 26) by the value in the cell in the same column 1 row above (row 27). 19 20 21 22 Boxes of cereal 2 6 11 15 23 Price per box $3.95 24 Total cost $7.90 $23.70 $43.45 $59.25 25