If t varies inversely with the speed, the formula for that is [tex]t= \frac{k}{r} [/tex]. If t = 2 and r = 40, then we can solve for k, the constant of variation. Multiply both sides by 40 to get k = 80. Now we need to find the value for t when r = 45. Using the k value we just solved for, we will fill in the equation as [tex]t= \frac{80}{45} [/tex] for a t value of about 1.78 hours
