we know that
the rate is equal to the speed
speed=distance/time
solve for the time
time=distance/speed
in this problem we have
speed=159.250 mph
distance=500 miles
substitute in the formula
time=500/(159.250)
time=3.1397 hours------> round to the nearest thousandth
so
time=3.140 hours
therefore
the answer is
3.140 hours