7th grade decimals and percentages

Example

A bike costs $220. In a sale it is 10% off. What is the sale price? (Type the number only.)

1. 10% × 220 = 22
2. 220 − 22 = 198

Answer: 198

Example

A restaurant bill is $87. The family adds a 15% tip. What is the total paid? (Type the number only.)

1. 15% × 87 = 13.05
2. 87 + 13.05 = 100.05

Answer: 100.05

Example

Increase 360 by 50%.

1. 50% × 360 = 180
2. 360 + 180 = 540

Answer: 540

Example

Decrease 400 by 50%.

1. 50% × 400 = 200
2. 400 − 200 = 200

Answer: 200

Example

A club's membership rose from 160 to 192. What is the percentage increase?

1. Increase = 32
2. 32 ÷ 160 × 100 = 20%

Answer: 20

Example

A pair of trainers costs $20. It is 10% off. What is the sale price? (Type the number only.)

1. 20 × 0.9 = 18

Answer: 18

Example

A sales tax of 20% is added to a $36 item. How much is the tax? (Type the number only.)

1. 20% × 36 = 7.2

Answer: 7.2

Example

A meal costs $20. The family leaves a 20% tip. How much is the tip? Round to the nearest cent. (Type the number only.)

1. 20 × 0.2 = 4
2. ≈ 4

Answer: 4

Example

A shop buys a T-shirt for $30 and marks it up by 40%. What is the selling price? (Type the number only.)

1. 40% × 30 = 12
2. 30 + 12 = 42

Answer: 42

Example

$3900 is saved at 4% simple interest per year. How much interest is earned in 6 years? (Type the number only.)

1. 3900 × 0.04 = 156
2. 156 × 6 = 936

Answer: 936

Example

Maya estimated there were 279 people at a concert. There were actually 310. What is the percent error?

1. |279 − 310| = 31
2. 31 ÷ 310 × 100 = 10%

Answer: 10

Example

What single number do you multiply by to increase an amount by 12%?

1. 112% = 1.12

Answer: 1.12