Two trains A and B start from Delhi and Patna toward Patna

Two trains A and B start from Delhi and Patna toward Patna and Delhi, respectively. After passing each other, they take 16 h and 9 h to reach Patna and Delhi, respectively. If the train from Delhi is moving at 90 km/h, then find the speed of the other train (in km/h) . ?

Given t₁ = 16 h , t₂ = 9 h and a = 90 km/h
According to the question
∴ Speed of B = a√t₁/ t₂
= 90 x √16/9
= 90 x 4/3
= 30 x 4 = 120 km/h