math 96 college intermediate algebra/geometry help needed!!

Question

Pairs of markings a set distance apart are made on highways so that police can detect drivers exceeding the speed limit. Over a fixed distance, the speed R varies inversely with the time T. In one particular pair of markings, R is 66 mph when T is 7 seconds. Find the speed of the car that travels the given distance in 6 seconds.

Answer 1

R = k/T

66 = k/7

k=462

R = 462/T

So then R = 462/6 = 77