Percent of Change

Percent of change – the ratio of the difference between the numbers to the original amount.

% of change = difference

original amount

*divide, then move the decimal to make

a percent

Find the percent of discount:

Original price: $100.00 New price: 70.00

Find the difference: 100 – 70 = 30

Make a ratio to the original: 30 100

Divide and move the decimal: .30 = 30 %

1) A popular brand of running shoes costs $68.00. If the store sells the shoes for $119.00, what is the percent of change?

2) Last year the chess club had 30 members. This year it has 24 members. What is the percent of decrease?

3) Alicia planted 45 tulip bulbs last year. This year she plans to plant 65 bulbs. What is the percent of increase?

4) A prom dress usually sells for $350.00. During May, the dress is on sale for $200.00. What is the percent of discount?

Answers: 1) 119 – 68 = 51 = .4285 = 42.9 % 119

2) 30 – 24 = 6 = .2 = 20 % 30

3) 65 – 45 = 20 = .3076 = 30.7% 65

4) 350 – 200 = 150 = .4285 = 42.9% 350