Question

If y varies directly as x, and y is 12 when x is 1.2, what is the constant of variation for this relation?

Answer 1

If you multiply 12 by 0.1, you get 1.2. To write this as a function you would say y is x multiplied by 0.1.
y=0.1x

Answer 2

B. 10

Explanation:

y = k x

12 = k 1.2

k = 12/1.2

k = 10