how many miles will be remaining after 62 minutes of driving?

Question

Tony is driving to san francisco. Suppose that the remaining distance to drive is a linear function of his driving time (mins). When graphed, the function gives a line with a slope of -0.8. Tony has 48 miles remaining after 50 mins of driving. How many miles will be remaining after 62 mins of driving?

Answer 1

y = -0.8x + b

48 = -0.8(50) + b

48 = -40 + b

88 = b

 

y = -0.8(63) + 88

y = -50.4 + 88

y = 37.6

 

Tony has 37.6 miles to go.