A monkey is trying to reach on top of a 30 meter high greasy electric pole in such a way, that it ascends by 2 meters in the first minute, it descends by 1 meter in the second minute, ascends by 2 meters in the third minute, descends by 1 meter in the fourth minute, and so on. If this fashion continues without break, after how many minutes of its start from the base of the electric pole, will the monkey be able to reach on the top of it?
(A) 60
(B) 57
(C) 56
(D) 48
(E) 30
Made Up!
fashion continues without break
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- sanju09
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+2 -1 +2 -1 .......... ==> So, in 2 minutes = 1 meter
1 meter = 2 minutes
28 meter = 56 minutes..
Now, it ascends 2 meter... So, 30 meter = 57 seconds
[spoiler]{B}?[/spoiler]
1 meter = 2 minutes
28 meter = 56 minutes..
Now, it ascends 2 meter... So, 30 meter = 57 seconds
[spoiler]{B}?[/spoiler]
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Good approaches friends
Another one...
In order to reach on the top of the pole, the last leap of the monkey must be an ascend (2-meter rise takes 1 minute), hence, let's focus on the time taken in reaching to the remaining 28 meters up the base.
Since it starts from an ascend of 2 meters in the first minute, and a descend of 1 meter in the next minute, hence, ideally, its rate is always 1 meter rise per 2 minutes. Hence, a 28 meters rise would take the monkey 56 minutes, add 1 minute of the last leap and answer [spoiler](B) 57.[/spoiler]
Another one...
In order to reach on the top of the pole, the last leap of the monkey must be an ascend (2-meter rise takes 1 minute), hence, let's focus on the time taken in reaching to the remaining 28 meters up the base.
Since it starts from an ascend of 2 meters in the first minute, and a descend of 1 meter in the next minute, hence, ideally, its rate is always 1 meter rise per 2 minutes. Hence, a 28 meters rise would take the monkey 56 minutes, add 1 minute of the last leap and answer [spoiler](B) 57.[/spoiler]
The mind is everything. What you think you become. -Lord Buddha
Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001
www.manyagroup.com
Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001
www.manyagroup.com