I need help with number 6

90 inches

Step-by-step explanation:

12" in a foot so in order to convert 3' to inches after Walt apply it by 12. once you have that just the formula to find the perimeter.

3 × 12 = 36

the perimeter formula is: 2L + 2W = P

36 × 2 = 72 9 × 2 = 18

72 + 18 = 90

your answer should be 90 inches.

a) 15/20 = 3/4

b) 12/20 = 3/5

c) 12/15 = 4/5

d) 10/15 = 2/3

So. It must be answer c).