When more than one symbol is used, the order becomes important. Excel performs calculations according to the BODMAS theory: Brackets over Division, Multiplication, Addition and Subtraction. This means that in a formula, anything in brackets will be calculated first, followed by division, multiplication, addition and subtraction.
The first example calculates the profit when 10 items are sold. These items were bought for £15 each and sold for £20 each. You would expect the answer to be £50 - £5 profit each x 10. See what happens if the order in which Excel calculates is ignored.
The selling price is subtracted from the buying price to give the profit per item and then multiplied by the total number of items - or is it? According to the answer in cell B4, there has been a loss of £130 made. This has happened because Excel has multiplied B2 by B3 and then subtracted B1. In order to get the correct answer, you must guide Excel, using the BODMAS theory.
The second example shows how brackets have been applied to ensure that the figure in C2 is first subtracted from C1 before the multiplication is carried out.