Problema Solution
A jet flew at an average speed of 480 mph from Point X to Point Y. Because of head winds, the jet averaged only 460 mph on the return trip, and the return trip took 25 minutes longer. How many hours was the flight from Point Y to Point X? How far is it from Point X to Point Y?
Answer provided by our tutors
Let S be the distance between X and Y.
We know that the average speed v =S/t where t is the time in hours. Thus t = S/v and we have
S/480 +25/60 = S/460
S/480 + 5/12 = S/460
S/460 - S/480 = 5/12
S(24 - 23)/11040 = 5/12
S = 5 * 11040 / 12
So
S = 4600 miles
t = 4600/460 = 10 hours
So the distance between X and Y is 4600 miles, it takes 10 hours for the jet to go from Point Y to Point X.