Big Ideas Math: Modeling Real Life, Grade 7
BI
Big Ideas Math: Modeling Real Life, Grade 7 View details
4. Percents of Increase and Decrease
Continue to next subchapter

Exercise 17 Page 257

Is the value of the new amount greater than or less than the value of the original amount?

Increase or Decrease? Decrease
Percent of Change: 12.5 %

Practice makes perfect

We want to tell whether each percent change is an increase or decrease. Then, we want to find the percent change. Let's do it one at a time.

Percent Increase or Percent Decrease

Recall that if a new amount is greater than the original amount, the percent change is called a percent increase. If the new amount is less than the original amount, the percent change is called a percent decrease. Consider the given amounts. Original Amount:&72 paper clips New Amount:&63 paper clipsWe can see that the new amount is less than the original amount, so the percent change is a decrease.

Finding the Percent Change

To determine the percent change p, we can use the following general formula. p % =Amount of change/Original amount From the given values, we can see the original amount was 72 and the new amount is 63. This is a decrease in the amount. Let's find the amount of decrease. 72- 63= 9 The difference between the original amount and the new amount is 9. Now we can use the formula.

Percent of change=Amount of decrease/Original amount
Percent of change=9/72
Percent of change=1/8
Percent of change=0.125
Percent of change = 12.5 %

The percent decrease is 12.5 %.