Q: A city’s population was 80,000 two years ago. If it increased by 10% each year, what is the current population?

$$80,000 \times 1.10 \times 1.10 = 96,800$$

Q: A company’s production was 65,000 kits two years ago. If production increased by 20% each year, what is this year’s production?

$$65,000 \times 1.20 \times 1.20 = 93,600$$

Question 1

A company’s revenue increased by 15% this year compared to last year, reaching $230,000. What was the company’s revenue last year?

Accepted Answer

$200,000

Question 2

A laptop originally priced at $1,200 is now being sold after a 25% decrease. What is the sale price?

Accepted Answer

$900

Question 3

A city’s population was 80,000 two years ago. If it increased by 10% each year, what is the current population?

Accepted Answer

$$80,000 	imes 1.10 	imes 1.10 = 96,800$$

Question 4

A medication’s price increased by 8% to $54. What was the original price?

Accepted Answer

$$54 \div 1.08 = 50$$

Question 5

A store marks down a jacket by 30%, and the sale price is $84. What was the original price?

Accepted Answer

$$84 \div 0.70 = 120$$

Question 6

A company’s production increased by 12% last year and then by 15% this year. If this year’s production is 129,920 units, how many units were produced two years ago?

Accepted Answer

$$129,920 \div 1.15 \div 1.12 = 100,000$$

Question 7

A car’s value decreased by 18% over the past year and is now worth $16,400. What was its value a year ago?

Accepted Answer

$$16,400 \div 0.82 = 20,000$$

Question 8

A rare book’s price increased by 25% to $250. What was the original price?

Accepted Answer

$$250 \div 1.25 = 200$$

Question 9

A company’s sales decreased by 12% this year to $44,000. What were last year’s sales?

Accepted Answer

$$44,000 \div 0.88 = 50,000$$

Question 10

A new phone’s price is $720 after a 20% increase. What was the price before the increase?

Accepted Answer

$$720 \div 1.20 = 600$$

Question 11

A hospital’s patient count increased by 5% each year for three years. If there are now 1,157 patients, how many were there three years ago?

Accepted Answer

$$1,157 \div 1.05 \div 1.05 \div 1.05 = 1,000$$

Question 12

A company’s expenses were reduced by 15% to $42,500. What were the expenses before the reduction?

Accepted Answer

$$42,500 \div 0.85 = 50,000$$

Question 13

A rare coin’s value increased by 40% over the past year and is now worth $1,400. What was its value a year ago?

Accepted Answer

$$1,400 \div 1.40 = 1,000$$

Question 14

A company’s production was 65,000 kits two years ago. If production increased by 20% each year, what is this year’s production?

Accepted Answer

$$65,000 	imes 1.20 	imes 1.20 = 93,600$$

Question 15

A pair of shoes is on sale for $135 after a 10% discount. What was the original price?

Accepted Answer

$$135 \div 0.90 = 150$$

Question 16

A business’s profit increased by 18% to $236,000. What was last year’s profit?

Accepted Answer

$$236,000 \div 1.18 = 200,000$$

Percent Increase and Decrease Problems in Algebra

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드