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Two donkeys are standing 400 meters apart. First donkey can run at a speed of 3 m/sec and the second can run at 2 m/sec. If two donkeys run towards each other after how much time (in sec) will they bump into each other?

Two donkeys are standing 400 meters apart. First donkey can run at a speed of 3 m/sec and the second can run at 2 m/sec. If two donkeys run towards each other after how much time (in sec) will they bump into each other? Correct Answer 80

Distance between two donkeys = 400 m

Speed of first donkey = 3 m/s

Speed of second donkey = 2 m/s

Relative speed, if both running opposite direction = 3 + 2 = 5 m/s

∴ Time taken to bump into each other = 400/5 = 80 sec

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