Calculating Percentages

Finding the total

Over the past week, 40% of the phone calls to Alicia's cell phone were from her son. Let's say you know that her son called her 12 times. Now you want to find out how many total calls she received. We can rewrite this example like this:

40% of ? = 12

This time we're missing the total—we don't know how many calls Alicia received.

Click through the slideshow to see how to find the total.

Try This!

Find the missing whole in each of these problems.

Four students are sharing an apartment. Each pays 25% of the rent. If each student pays $200 per month, how much is the total rent for each month?

Jill has a 25% off coupon for some computer software. If the coupon saved her $35, how much would the software cost without the coupon?

Allen paid $12 in interest on his credit card this month. If you know that the interest rate on his card is 6%, how much was the total amount on his card?