6th Grade Math Textbook, Progress

Percent Change

Subtract the original price from the new

price to find the amount of increase.

Percent change is the ratio of the change to the

original price expressed as a percent.

A $25 shirt is on sale for $20. What is the percent

decrease in price?

To find the percent decrease, use a proportion.

Let d
rate of decrease

 $5  100 
$25d 
 20 
d

So 
 
20%

The decrease in price is 20%.

Last month the skateboard that Joe wanted cost $40. This month

the skateboard costs $50. What is the percent increase in price?

To find the percent increase, use a proportion.

Let i
rate of increase

i

i

i
0.25
25%

The increase in price is 25%.

Find the percent decrease or increase.

1. $45 decreased by $9 2. $85 decreased by $42.50 3. 120 decreased by 54


2. 828 decreased by 289.8 5. 316 decreased by 28.44 6. $32 increased by $8


3. $62 increased by $18.60 8. 648 increased by 486 9. 153 increased by 15.3

Find the percent change. Explain whether it is a decrease or increase.

10. from $346 to $269.88 11.from 1295 to 1036 12. from $1022 to $715.40


11. from $525 to $603.75 14.from 3950 to 4937.5 15. from $9696 to $12,895.68

$10

$40

$50 
$40

$40

increase

original price

d

100

$5

$25

$25d

$25

$500

$25

d

100

$5

$25

d

100

$25 
$20

$25

decrease

original price

$0 $20 $25

0% d 100%

Subtract the sale price from the original

price to find the amount of decrease.

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