Answer:
C is the only choice that forms a proportion
Step-by-step explanation:
a. 24/31, 20/27
(31 is prime)
b. 8/9, 24/36
(this one doesn't work since it would have to be 3/4) which isn't a proportion
c. 16/5, 64/20
(both 16/5 *4 = 64/20) so it works
d. 6/4 , 15/10
(similar situation to choice b the ratio wont work since 6 doesn't go into 15)
