Two trains P and Q whose front ends are 539 km apart. They start at the same time towards each other and cross each other after 200 minutes… — Answer & Discussion

Two trains P and Q whose front ends are 539 km apart. They start at the same time towards each other and cross each other after 200 minutes. The ratio of length of these trains is 3 ∶ 2 and their speeds are 90 km/hr and 72 km/hr. Find the difference of the length of these two trains.

A50 m
B250 m
C100 m
D200 m

Answer not set

Join the discussion Report an error

Discussion 1

CCommunity15 Jul 2019

Given the ratio of length of these trains is 3 ? 2

Suppose the lengths of the trains are ‘3x’ and ‘2x’ km

⇒ [539 + 3x + 2x] / [90 + 72] = 200/60

⇒ 539 + 5x = 540

⇒ 5x = 1

⇒ x = 0.2

⇒ Lengths of the train = 600 m and 400 m

∴ Difference of the length of two trains = 600 – 400 = 200 m