Question

Two trains start at the same time from opposite ends of a 200 mile track, going towards each other at 40mph each. A sparrow takes off from the first train's engine at 50mph at the exact time the trains start, flying towards the other train. It touches the second train's engine, and immediately heads back to the first train. It continues doing this until the trains crash. How many miles did the sparrow fly?

Answer 1

Dear Mahima,

◆ Answer -

Distance sparrow flew = 125 miles

● Explanation -

Here, length of trains is not given, so that must be assumed negligible.

Trains are moving at same speeds, thus they will crash in the midpoint of track i.e. 200/2 = 100 miles.

Time taken by each train to reach midpoint is -

t = 100 / 40

t = 2.5 h

Sparrow is flying from the time trains start till trains crash. i.e. 2.5 h.

Distance travelled by sparrow in this time -

s = 50 × 2.5

s = 125 miles

Thus, the sparrow flew for about 125 miles.

Thanks for asking..