A 110 m long train crosses a 340 m long bridge in 45 seconds. What time will it take to cross a platform 250 m long?

48 sec

Total Distance (d₁ : d₂) = (110 + 340) : (110 + 250) = 450 : 360 = 5  :  4

As speed is same, then ratio of time & distance will be directly proportional.

Therefore,

d₁ : d₂ = t₁ : t₂ = 5  :  4

5R = 60 sec.

1R = 12 sec

4R = 4 × 12 = 48 sec.