word Problem

Question

A jet flew at an average speed of 480mph from Point X to Point Y. Because of head winds, the jet averaged only 460mph of the return trip, and took him 45min longer. How many hours was the flight from Point Y to X? How far is it from Point X to Point Y?

Answer 1

Let t = time it takes to go from point X to point Y

 

Then, t + 0.75 = time to go from Y to X  (45 min = 0.75 hr)

 

Distance = (Rate)(Time)

 

Since the distance from X to Y is the same as the distance from Y to X,

 

we have:  480t = 460(t+0.75)

 

               480t = 460t + 345

 

                 20t = 345

 

                    t = 17.25 hours 

 

Time from Y to X = t + 0.75 = 18 hours

 

One-way distance = 460(18) = 8280 miles

 

 

Answer 2

distance travelled from point X to point Y = s

time travelled = distance/speed = s/(480) +3/4 = s/(460)

X/460 -X/480 = 3/4

480s - 460s = 3/4(480)(460)

20s = 165600

x = 8280 miles