Math Exam on Ratios

A backyard pond has 12 sunfish and 30 rainbow shiners. Write the ratio of sunfish to rainbow shiners in simplest form .

• 12:30

• 2:5

• 18:30

• 3:5

Which sentence accurately represents the following ratio:

• The ratio of moons to suns is 4 to 8

• There are 4 moons for every 8 suns

• There are 4 moons for every 2 suns

• The ratio of suns to moons is 2:1

In the fruit bowl there are 4 apples, 2 bananas, and 5 pears.  What is the ratio of pears to ALL fruit?

• 5:4

• 5:11

• 2:5

• 6:5

A ratio is...

• the difference between two numbers.

• a comparison of two numbers by division.

• a comparison of two numbers by multiplication.

• the sum of two numbers.

If the ratio of boys to girls in a class is 5:6 and there are 30 girls, how many boys are there?

• 25

• 20

• 24

• 28

What is the ratio of 30 minutes to 2 hours?

• 1:4

• 1:2

• 15:1

• 1:8

If the ratio of cats to dogs in a pet store is 3:4, and there are 12 cats, how many dogs are there?

• 16

• 14

• 18

• 20

If the ratio of cats to dogs is 3:4, how many cats are there if there are 20 dogs?

• 15 cats

• 25 cats

• 30 cats

• 10 cats

If the ratio of red balls to blue balls in a bag is 5:3, how many blue balls are there if there are 20 red balls?

• 12

• 15

• 8

• 10

Answer explanation

If the ratio of red balls to blue balls is 5:3, and there are 20 red balls, set up an equality like this: 5/3 = 20/x. To get from 5 in the left numerator to 20 in the right numerator, multiply 5*4. Since the numerator is multiplied by 4, the denominator would also be multiplied by 4. 3*4 = 12.

• 60

• 65

• 70

• 75