Question

2
Paul reaches office from home 12 before, if he goes at a speed of 15 kmph. He reaches office 20
minutes late if he travels at a speed of 9 kmph. Find the distance between his office to home?​

Answer 1

Step-by-step explanation:

To find the distance,

Let distance = x km.

Time taken at 3 kmph : dist/speed = x/3 = 30 min late.

time taken at 4 kmph : x/4 = 40 min earlier

difference between time taken : 40-(-30) = 70 mins = 70/60 hours.

x/3- x/4 = 70/60

x/12 = 7/6

x = 14 km.

So option B is the correct answer.

Answer 2

Answer:

Step-by-step explanation:

To find the distance,Let distance = x km.

[Here using, Time=Distance/Speed]

Time taken at 9 kmph : dist/speed = x/9 = 20 min late.

time taken at 15 kmph : x/15 = 12 min earlier

difference between time taken : 12-(-20) = 32 mins = 32/60 hours

=> x/9- x/15 = 32/60

=> 2x/45=32/60

=> x = 12 km.