Add them all up to get the answer
Well first I think you need to divided <span />
T = k/R where k is the constant of variation, T=time and R=speed.
Plug in the given values:-
12 = k/60
k = 12*60 = 720
So the equation of variation is T = 720/R
At 85 mph we have
T = 720 / 85 = 8.47 hours (answer)
10 books cost $30. To figure it out, it's just 3 times the number of books. XD
