shivansh9307 wrote:
Rohan, Shikha's boyfriend, had to pick her from her home for a live concert on her 23rd birthday. The venue of the concert and Shikha's home were in opposite directions from Rohan's office. He got late because of some work at the office and realized that if he goes to pick Shikha from her home, which was a 48-minute drive from his office, they would be late for the show by 16 minutes. He asked her to start from her home towards his office in an auto-rickshaw and himself started driving towards her home. Both of them started simultaneously, he picked her as soon as they met and they managed to reach the venue just in time for the concert. If Rohan drives at an average speed of 60 km/hr, find the speed (in km/hr) of the auto-rickshaw.
A. 16
B. 20
c. 12
d. 15
e. None of these
Source- GMAT avengers group FB
Rohan's speed is 60 kmph so he takes 1 min for every 1 km. Since he takes 48 min to reach Shikha, her house is 48 km away from his office.
If he goes to pick her up,
S <--------------48 km----------------- R
----------------------------------------->
he takes 96 mins to pick and reach back.
But if she also travels some distance, he takes 16 mins less.
S ===8====><---------------40------------R
==========------------------------------>
So he would not have travelled the last 8 kms to her house to and fro. So the auto would have travelled the 8 kms.
Since this is done in same time,
Ratio of Speeds = Ratio of distances
s/60 = 8/40
s = 12 kmph
Answer (C)