Question

Type the missing number to complete the proportion.

21 plants in 7 rows = 39 plants in ? rows

Answer 1

13 rows

Explanation:

We can write a proportion to solve

21 plants 39 plants

---------------- = ---------------

7 rows x rows

Using cross products

21x = 7 * 39

Divide each side by 21

21x/21 = 7 * 39/21

x =13