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Two trains, each having a speed of 22 km/h, are headed at each other on the same straight track. A bird that can fly 60 km/h flies off the front of one train when they are 51 km apart and heads directly for the other train. On reaching the other train it flies directly back to the first train, and so forth. (We have no idea why a bird would behave in this way.) What is the total distance the bird travels before the trains collide

User Hetsgandhi
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1 Answer

3 votes

Answer:

the total distance the bird travels before the trains collide is 69.54 km

Step-by-step explanation:

Given the data in the question,

dA = 22km/h × t

dB = 51km - 22km/h × t

now we find the time, when the two trains collide

dA = Db

22km/h × t = 51km - 22km/h × t

44km/h × t = 51km

t = 51km / 44km/h

t = 1.159 hrs

so the bird can fly back and forth for 1.159 hrs before the train collide.

hence, distance travelled by the bird in total will be;

d = v × t

we substitute

d = 60 km/h × 1.159 h

d = 69.54 km

Therefore, the total distance the bird travels before the trains collide is 69.54 km

User Juan Sebastian
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