Question

which pair of ratios forms a proportion? hint: check for cross products. a. 6/9=9/12 b. 8/16=10/21 c. 6/15=10/25 d. 4/14=6/27

Answer 1

c. 6/15 = 10/25

Explanation:

Using the hint, we can form the cross products of the offered choices:

a. 6(12) vs 9(9) ⇒ 72 vs 81 . . . not a proportion

b. 8(21) vs 16(10) ⇒ 168 vs 160 . . . not a proportion

c. 6(25) vs 15(10) ⇒ 150 vs 150 . . . IS A PROPORTION

d. 4(27) vs 14(6) ⇒ 108 vs 84 . . . not a proportion

__

The cross products are the same for choice C, so that is a pair of ratios that form a proportion:

6/15 = 10/25