Pairs of markings, a set distance apart, are made on highways so that the police can detect drivers exceeding the speed limit. Over a fixed distance, the speed R varies inversely with the time T. For one particular pair of markings, R is 35mph when T is 6 seconds. Find the speed of a car that travels the given distance in 5 seconds.

Question

R= ___ mph
(round to the nearest whole number.)

Answer 1

inverse variation means that RT = k, a constant.

So, just set up things which are both equal to k:

35*6 = R*5

now just find the R value.