Which pair of ratios forms a proportion?
a. 11/36, 121/180
b. 13/21, 39/63
c. 14/23, 70/92
d. 20/51, 4/5

which ratio forms a proportion with 4/5

a. 2/3
b. 4/10
c. 16/20
d. 16/25

Proportions are two ratios that are equal. Therefore, from the choices listed above the correct answer for question one is option B. The two ratios are equal because when you simplify further the second ratio it will have a value of 13/21 also. For question 2, the correct answer is D. Simplifying it will yield a value of 4/5.