Percent Increase and Decrease with Equations Practice Problems

A pair of designer sneakers was purchased for $120. Since they were purchased, their price has increased by 15%. What is the new price?

• $130

• $135

• $138

• $140

Draw a diagram to represent each situation: The number of miles driven this month was a 30% decrease of the number of miles driven last month. The amount of paper that the copy shop used this month was a 25% increase of the amount of paper they used last month.

Elena’s aunt bought her a $150 savings bond when she was born. When Elena is 20 years old, the bond will have earned 105% in interest. How much will the bond be worth when Elena is 20 years old?

• $300

• $307.50

• $315

• $320

• 20%

• 25%

• 30%

• 15%

A stock increases in value by 5% from $100 to what value?

• $105

• $110

• $95

• $100.50

A population of 5000 increases by 10% in a year. What is the new population?

• 5500

• 6000

• 500

• 4500

If a shirt originally costs $50 and is marked down by 20%, what is the new price?

• $40

• $30

• $45

• $35

If a population of 5000 increases by 10% in a year, what will be the population after one year?

• 5500

• 6000

• 5050

• 6500

A population of 500 increases by 10% in a year. What is the new population?

• 550

• 600

• 510

• 500