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In this lesson, you will calculate how long you spent on all of the activities you recorded in the last video.

This will show you how much time you use and how much extra time you can spend on anything you want, like making more time for your friends or picking up an after-school job.

To make your calculations, you will use a SUM formula.

A sum formula in a spreadsheet adds all the numbers in a range of cells.

Adding up a long list of numbers is repetitive.

and, it takes a really long time.

Using a formula in a spreadsheet helps you calculate numbers more quickly and accurately.

To begin, add “Total” beneath the list of activities and times.

Use the sum formula to add up the time in the “hours” column.

All formulas begin with an Equals sign.

Type Equals and SUM.

Select the sum formula from the list.

Then, select the range of cells that contain hours.

Press Enter.

The total automatically calculates.

Repeat the sum function for your “minutes” column.

The sum formula will show the total time you spent yesterday.

If your minutes column is over 60 , convert the minutes into hours.

To do this, use a “cell reference” for the total hours you spent yesterday.

The cell reference is the row and column code for the cell, like the “address” for the cell.

Type the equals sign.

Then, enter the cell reference for your “minutes” total.

Divide the total number of minutes by 60 to convert minutes to hours.

Finally, add your total hours spent to the minutes you converted to hours to see exactly how much time you spent on the activities you listed.

Select the cell with minutes converted to hours.

Type a plus sign and select the cell with hours.

Press Enter.

If your total is more than 24, you may have overestimated how much time you spent on a particular task.

Maybe you included two hours for babysitting your brother and an hour of practicing the guitar, but you actually did these at the same time.

Remove a task or reduce the time spent in a particular activity.

Your totals will update automatically since you used formulas and cell references.

Then, move on to the next video to figure out how much time you have left over.

Now, it’s your turn: Calculate how many hours you spent yesterday, Add up the minutes you spent separately, and convert your spent minutes into hours.


  1. Calculate how many hours you spent yesterday.
  2. Add up the minutes you spent separately.
  3. Convert your spent minutes into hours.