Two buses are travelling on the highway from X to Y

[guerrero]

Two buses are travelling on the highway from X to Y . The speed of the first bus is 60KMPH and the second bus travels at the speed of 40KMPH. The first bus leaves at 11 AM and the second leaves 15 mins later. The first bus starts back for X, 15 mins after it reaches Y . How far from Y will the first Bus meet the second ?Also, after how much time will they meet each other after the departure of the first bus from X , if the distance between X and Y is 180 KM.

A)36 KM , 3 Hrs 36 Mins
B)36 KM, 3 Hrs 51 Mins
c)24KM, 3 Hrs 50 mins
d)24 KM, 3 hrs 51 mins
e)48 KM, 2 Hrs 51 mins

OA B

[srcc25anu]

Distance = 180kms
Bus A takes 3 hours to cover 180 kms (go from X to Y)
Bus B takes 4.5 hours to go from x to Y
Now Bus A Starts from X at 11:00 AM, reaches Y at 2:00 PM, waits for 15 mins and starts to return to Point X at 2:15 PM
Bus B starts from point X at 11:15Am and until 2:15PM, it covers 40*3 = 120 Kms
AT 2:15PM, 2 buses are 60 Kms apart and their relative speed = 100 kms as they are travelling in opposite directions)
Time it will take Bus A and B to meet = 60 KMS /100 KM/Hr or 36 mins
In 36 mins Bus A will have travelled 36 * 60 / 60 kms = 36 KMS
Therefore the 2 buses meet 36 kms away from Point Y

And the 2 buses will meet at 2:15 + 36 mins = 2:51PM
Time from 11:00Am to 2:51PM = 3 hrs 51 Mins

Ans B

[inavdeep]

Option B

[vipulgoyal]

Shorter way
at 3;15 hours A will start from Y
now match time and KM from ans choices 3;15 + ;36 = 3;51