The amount of money that Sarah earns varies directly with the number of hours worked. If Sarah earns $320 for working 40 hours, determine the constant of proportionality.

Question

(1 point)
A. 9
B. 8
C. 7
D. 6

Answer 1

To solve this problem, we need to set up a proportion using the given information.

Let x be the constant of proportionality. We are told that the amount of money Sarah earns varies directly with the number of hours worked.

So, we can set up the following proportion:

320/40 = x/1

To solve for x, we can cross-multiply:

320 * 1 = 40 * x

Simplifying the equation:

320 = 40x

Divide both sides by 40:

x = 320/40

x = 8

Therefore, the constant of proportionality is 8. The correct answer is B.