Question

A train will leave in 17 minutes from a station. Four friends have only one umbrella to catch the train. Only two can be accommodated in that one umbrella. Alone A takes 1 minute to catch the train. Alone B takes 2 minutes to catch the train. Alone C takes 5 minutes to reach the train. Alone D takes 10 minutes to catch the train. How does all reach the train on time without getting wet?

Answer 1

Given:

A = 1 mins

B = 2 mins

C = 5 mins

D = 10 mins

To Find:

The sequence that they would go to the station so that they make it in 17 minutes.

Solution

A and B go to the station

Time taken = slower of the 2

Time taken = B

Time taken = 2 mins

B goes back

Time taken =  2 mins

Total time taken = 2 + 2

Total time taken = 4 mins

C and D go to the station

Time taken = slower of the 2

Time taken = D

Time taken = 10  mins

Total time taken = 4 + 10

Total time taken = 14 mins

A goes back

Time taken =  1 mins

Total time taken = 14 + 1

Total time taken = 15 mins

A and B go the station

Time taken = slower of the 2

Time taken = B

Time taken = 2  mins

Total time taken = 15 + 2

Total time taken = 17  mins

Answer 2

Answer:

hope it is helpful.........