Percent and Ratio Practice Questions

1. Rick renovated his home. He made his bedroom 40% larger (length and width) than its original size. If the original dimensions were 144 inches by 168 inches, how big is his room now if measured in feet?
1. 12 ft x 14 ft
2. 16.8 ft x 19.6 ft
3. 4.8 ft x 5.6 ft
4. 201.6 ft x 235.2 ft
1. \$36.00
2. \$47.60
3. \$40.00
4. \$42.50
1. 6/15
2. 15/6
3. 3/5
4. 2/3
1. \$141.60
2. \$225.70
3. \$305.30
4. \$330.40
1. 1/4
2. 1/10
3. 3/5
4. 1/20
1. 7%
2. 13%
3. 65%
4. 80%
1. 70
2. 238
3. 270
4. 340
1. 3
2. 10
3. 27
4. 30
1. \$25640
2. \$25970
3. \$26640
4. \$26970
10. In order for a school to allow a vending machine to be placed next to the cafeteria, 65% of the school’s population must ask for it. If 340 of the school’s 650 students have requested the vending machines, how many more are needed to get the vending machines?
1. 75
2. 83
3. 89
4. 99

1. B

144 X 0.40 = 57.6 + 144 = 201.6 and 168 X 0.40 = 67.2 + 168 = 235.2;
then convert to feet 201.6/12 = 16.8 ft and 235.2/12 = 19.6 ft.

2. C

If X represents the original price of the jacket and Y represents the discounted amount, then 0.30X = Y and X – Y = 28; X – 0.30X = 28; 0.70X = 28; X = = 40.

3. C

The number of jobs he did not get is 15 – 6 = 9. The ratio is 9:15 or 3:5.

4. D

The television is 30% off its original price of \$472. 30% of 472 is 141.60, and 141.60 subtracted from 472 is 330.40. Thus, Gordon pays \$330.40 for the television.

5. C

According to the problem statement, 60% of the class wanted to work with the elderly. Therefore, convert 60% to a fraction by using the following steps:
60% = 60/100
Now simplify the above fraction using a greatest common factor of 20.
60/100 = 3/5

6. B

Since 35% of the staff will take vacation days, only 100% – 35% = 65% of the staff is available to work. Of the remaining 65%, only 20% are certified to work in the neonatal unit. Therefore multiply 65% by 20% using these steps:
Convert 65% and 20% into decimals by dividing both numbers by 100.
65/100 = 0.65 and 20/100 = 0.20
Now multiply 0.65 by 0.20 to get (0.65)(0.20) = 0.13
Now convert 0.13 to a percentage by multiplying by 100.
0.13)(100) = 13%

7. B

The patient’s dosage must decrease by 30%. So calculate 30% of 340:
(0.30)(340 mg) = 102 mg
Now subtract the 30% decrease from the original dosage.
340 mg – 102 mg = 238 mg

8. C

Since 70% of the patients in the study were women, 30% of the patients were men. Calculate the number of male patients by multiplying 100 by 0.30.
(100)(0.30) = 30
Of the 30 male patients in the study, 10% were overweight as children. So 90% were not overweight. Multiply 30 by 0.90 to get the final answer.
(30)(0.90) = 27

9. C

Susan receives \$40,000. First she contributes 10% of her salary to a retirement account. (\$40,000)(0.10) = \$4000
\$40,000 – \$4000 = \$36,000
After contributing to her retirement account, Susan has \$36,000 left. Then she pays 25% in taxes.
(\$36,000)(0.25) = 9,000
\$36,000 – \$9,000 = \$27,000
After paying taxes, Susan has \$27,000 left. Finally, she pays \$30 each month for health insurance. Calculate the annual amount Susan pays for health insurance, and subtract this amount from her remaining salary.
(\$30)(12) = \$360
\$27,000 – \$360 = \$26,640

10. B

(650 students x .65 = 422.5) 422.5 – 340 = 82.5 ≈ 83 more students