Question

Which ratio can be used to form a proportion with the given ratio?

7 to 12

A.
8 to 13

B.
10 to 15

C.
14 to 19

D.
21 to 36

Answer 1

D.
If you multiply both numbers in the given proportion by 3, you get answer D:
7 x 3 = 21
12 x 3 = 36.
Because you can multiply both of the numbers in the given ratio by the same number (3) to get the ratio in answer D, they are a proportion.

Answer 2

7 / 12 = 0.583333333

Divide them all to see which one equals 0.583333333.

A.

8 / 13 = 0.615384615

B.

10 / 15 = 0.666666667

C.

14 / 19 = 0.736842105

D.

21 / 36 = 0.583333333

Therefore, your answer is D.