Question

If x and y are in direct proportion and y is 72 when x is 12, find y when x is 10.

Answer 1

y = 60 when x is 10

Explanation:

x and y are in direct proportion

x : y

x = k * y (where k is the constant of proportionality)

y is 72, when x is 12

12 = k * 72

k = 12/72 = 1/6

find y when x is 10

x = k * y

10 = k * y

10 = 1/6 * y

y = 10 * 6 = 60