Answer:
The constant of variation is 5.
Step-by-step explanation:
In direct variation, as y varies directly with x, the standard equation is
y = kx,
where k is the constant of variation.
In your case, we use R and S. R varies directly with S, so we have
R = kS
We know that when S = 16, R is 80, so we plug in those values and solve for k, the constant of variation.
R = kS
80 = k(16)
k = 80/16
k = 5
