# 9.4.1 Finding the Balance

## Activity: Finding the Balance

Formulas have also been used to calculate the total monthly expenses and the balance. If you were working these calculations out by hand, what would you do? Check by comparing your answers with the values in cell B13 and B15.

Try to write down the formulas for these cells in the form “value in B13 = …” To calculate the total monthly expenses, you need to add the individual expenses on “Rent,” “Food,” “Transportation,” “Regular Bills,” and “Other.” The formula will be:

To find the balance, you need to take the expenses away from the total income. So, the new formula will be:

Did your formulas give you the correct answers?

To put these formulas in the spreadsheet, you can type the formula directly into the relevant cell, starting with an equals sign to show that you are entering a formula rather than a word. Notice that in cell B13, a shorthand form for the sum has been entered. You could have typed in “= B8 + B9 + B10 + B11 + B12” but it is also acceptable to use the shorthand form, “= SUM(B8:B12)”, which is shown here. This instruction tells the computer to add the values in all the cells from B8 to B12.

One of the advantages of using a spreadsheet is that if you change some of the numbers, all the calculations that use that particular number will be automatically updated to reflect the change. For example, in this budget, the amounts for the salary, rent, and the regular bills are likely to remain the same from one month to the next and may only be updated once or twice a year. However, the amounts for food, transportation, other bills, and other income probably will change from month to month. These values can be changed easily on the spreadsheet and the revised balance produced immediately.