Ch. 8 Math Test Study Guide

1

100

Convert the percent to a decimal.

5.3%

0.053

200

Find 90% of 650

585

300

Jacob walked 1/5 of the 125 dogs at the shelter. What percent of the dogs did he walk, and how many dogs did he walk?

1/5 = 20%

25 dogs

400

Give the percent setting to obtain each enlargement or reduction.

1 2/5

140%

500

Find the sale price of a $400 suit discounted 35%

100% - 35% = 65%

400 x 0.65 = $260

2

100

Convert the percent to a decimal.

225%

2.25

200

What number is 140% of 12?

140% x 12

1.4 x 12 = 16.8

300

15% of n = 36

0.15n = 36

n = 240

400

Using a copier setting of 125%, what are the new dimensions of a 20.4 cm x 25.4 cm photo? Do not round answers.

1.25 x 20.4 = 25.5 cm

1.25 x 25.4 = 31.75 cm

500

Find the original price of a scooter purchased for $280 after a 30% discount.

100% - 30% = 70%

0.7n = 280

n = $400

3

100

Write the decimal as a percent

0.5

50%

200

Find the 6% sales tax on a price of $27.

0.06 x 27 = $1.62

300

Find the interest.

loan: $2500

rate: 6%; time: 1 year

I = 2500(0.06)(1) = $150

400

Find the percent change. Round to the nearest percent. Specify an increase or decrease.

original amount: 40

new amount: 52

52 - 40 = 12

12/40 = 3/10 = 30% increase

500

An 8 in. figure is copied at 60%, and then the copy is copied at 90%. What size is the final copy of the figure?

8(0.6)(0.9) = 4.8(0.9) = 4.32 in.

4

100

Write the decimal as a percent.

3.2

320%

200

What percent of 75 is 18? Use a proportion to solve.

24%

300

Find the interest.

savings account: $3000

rate: 4%; time: 2 years

I = 3000(0.04)(2) = $240

400

Find the percent change. Round to the nearest percent. Specify an increase or decrease.

original amount: 109

new amount: 139

139 - 109 = 30

30/109 = 0.275 = 28% increase

500

Find the sale price of a 20% discount off a $150 camera with an additional 10% off.

100% - 20% = 80%

0.8(150) = $120

100% - 10% = 90%

0.9(120) = $108

5

100

Write as a fraction

32 1/2%

13/40

200

75% of what number is 60? Use a proportion to solve for the missing whole.

80

300

Find the total cost of the purchase.

a purse: $57

tax: 5%

100% + 5% = 105% = 1.05

n = 1.05 x 57

n = $59.85

400

Find the discount amount of a $25 item at 30% off.

25 x 0.3 = $7.50

500

After purchasing a truck for $10,500, a dealer marks the price up 40%. A salesman sells the truck during a 10% off sale. How much does the salesman make if he is paid 3% of the sale price?

0.4(10,500) = 4200

10,500 + 4200 = 14,700

0.1(14,700) = 1470

14,700 - 1470 = 13,230

0.03(13,230) = $396.90