A monkey is climbing a rope of length 100 m. He climbs 3 m in one minute and slips down by 1 m in another one minute because of rope being slippery (It takes him complete one minute time to slip down by 1 meter). Now again he climbs 3 m in one minute and in another one minute slips down by 1 m. This climbing and slipping continues till he reaches the top of the rope. How much time he takes to reach the top of the rope.
100 minutes
1 hr 40 minutes and 40 seconds
1 hr 38 minutes and 40 seconds
None of the Above
Cannot be determined
Answer :1 hr 38 minutes and 40 seconds
Solution (Fast Approach)
In 1 minute Monkey is climbing 3 m. In second minute he is slipping down by 1m. Hence in 2 minute he covers 2 m.
In 98 minutes he covers 98 m
Now he had only 2 m left.
Total time in climbing 2 m = 2/3 min = 2/3 * 60 = 40 seconds (He will not slip further)
hence Monkey takes 98 min 40 seconds = 1 hr 38 min 40 seconds to climb the rope
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