Question

Ram, Shyam and Hari went out for a 100 kilometre journey. Raman and Hari started the journey in Ram's car @ 25 km per hour while Shyam walked at the rate of 5 km per hour .After sometime Hari got off and started walking at the rate of 5 km per hour and Ram went back to pick up Shyam. All three reached the destination simultaneously. The number of hours required for the trip was???

A) 8
B) 7
C) 6
D) 4

Answer 1

Answer:

n first  T  hrs

Ram & Hari Covered  =  25T  km

Distance Remained = 100 - 25T  km

Time taken by Hari to Cover 100 - 25T  km  = (100 - 25T)/5

= 20 - 5T  hrs

Total Trip time = T  + 20 -5T  = 20 - 4T hrs

Distance Covered by Shayam in T hrs  = 5T  km

Distance between Shayam  & Ram  = 25T - T  = 20T  km

Time taken to Cover 20T km  By Ram & Shayam

= 20T/(25 + 5)

= 2T/3  Hrs

Remaining Time = Time Taken by Hari  - 2T/3  Hrs

(20 - 5T)  - 2T/3   = 20  - 17T/3  hr

Distance Covered by  Shayam  =  5T  +  5 (2T/3)  = 25T/3  km

Remaining Distance = 100 - 25T/3  km

25(20  - 17T/3)  = 100 - 25T/3

=> 500  - 425T/3  = 100 - 25T/3

=> 400 = 400T/3

=> T = 3 Hrs

Total Trip time  = 20  - 4 * 3  =  8  hrs

Step-by-step explanation:

ans a)8