Question

The value of y varies directly with x, and y = 6 when x = 18, how do you find y when x = 12?

Answer 1

When x = 12, y = 4.

Explanation:

If `y prop x` we can write that `y = k*x` where k is a constant of proportionality.

Using the values given:

`6 = 18*k implies k = 1/3`

`y = 1/3*12 = 4`