is true proportion? A. 2 : 3 = 3 : 2 B. 42 : 7 = 6 : 2 C. 3 : 5 = 12 : 20 D. 14 : 6 = 28 : 18

Question

 

2. Which one of the following statements expresses a true proportion?

A. 2 : 3 = 3 : 2

B. 42 : 7 = 6 : 2

C. 3 : 5 = 12 : 20

D. 14 : 6 = 28 : 18

Answer 1

Imagine if they were fractions, so 2:3 would be 2/3 and so on.

The question is asking if any of those equalities (like 2:3 = 3:2) are true.

A) 2/3 = 3/2

Multiply both sides by 6:

4 = 9

Not true.

B) 42/7 = 6/2

6 = 3

Not true.

C) 3/5 = 12/20

Multiply both sides by 20

12 = 12

True

D) 14/6 = 28/18

Multiply both sides by 18

42 = 28

Not true

The only true one is C.

Answer:  C.

Answer 2

A. (2 / 3 = 3 / 2) = False

B. (42 / 7 = 6 / 2) = False

C. (3 / 5 = 12 / 20) = True

D. (14 / 6 = 28 / 18) = False