Applications of PercentApplications of Percent

Section 7.4

The freshman class of 450 students is 36% of all students at State College. How many students go to State College?

State the problem in words, then translate State the problem in words, then translate to an equation.to an equation.

Equation MethodEquation Method

In words:In words: 450 is 36% of what number?

Solve:Solve: 450 0.36x

Translate:Translate: 450 36% • x

2Martin-Gay, Prealgebra, 5ed

The freshman class of 450 students is 36% of all students at State College. How many students go to State College?

State the problem in words, then translate State the problem in words, then translate to a proportion.to a proportion.

Proportion Equation MethodProportion Equation Method

In words:In words: 450 is 36% of what number?

Translate and Solve:Translate and Solve:

amount basepercent450 36

100b

3Martin-Gay, Prealgebra, 5ed

Percent Increase Percent Increase Percent DecreasePercent Decrease

percent increasepercent increase

percent decreasepercent decrease

In each case write the quotient as a percent.In each case write the quotient as a percent.

amount of increase

original amount

amount of decrease

original amount

Helpful HintHelpful HintMake sure that this number in the denominator is the original number and not the new number.

4