Question

A round trip from Montreal to LA is 2,688 miles and takes an airline 9 hours and 20 minutes. Given the outbound trip is the same distance as the return trip, and the speed of the plane was 25%faster on the return trip, how long did the return trip take? Answer to the nearest minute. ​

Answer 1

Answer:

4.074 hours

Step-by-step explanation:

r =

The formula for speed = Distance × Time

Hence,

Let the outbound speed = r

return trip speed = r + 25x/100 = 125r/100 = 1.25r

Note that: 9 hours and 20 minutes = 9.167

Let t1 and t2 be the time taken to travel on way and return journey.

t1 + t2 = 9 hr 10 min = 9.167 hrs

Hence:

2688/r + 2688/1.25r = 9.167

LCM(1.25r)

(2688 × 1.25) + 2688 /1.25r= 9.167

3360 + 2688 = 9.167 × 1.25r

6048 = 11.45875r

r = 6048/11.45875

Outbound trip rl = 527.8062615904876mph

Return trip speed = r + 25x/100 = 125r/100 = 1.25r

= 1.25 ×

659.75782699mph

Time for return trip = Distance/Speed

= 2,688 miles/659.75782699mph/

= 4.0742222222 hours

Approximately = 4.074 hours