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by romitvsingh » Tue Nov 22, 2011 12:34 am
In how many ways can 5 letters be posted in 3 post boxes, if any number of letters can be posted in all of the three post boxes?

(A) 5 C 3
(B) 5 P 3
(C) 53
(D) 35
(E) 25
pls explain in detail
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by neelgandham » Tue Nov 22, 2011 3:16 am
The first letter can be posted in any of the 3 post boxes.Therefore the number of choices is 3. In the same way, the second, the third, the fourth and the fifth letter can each be posted in any of the 3 post boxes.Therefore, the total number of ways the 5 letters can be posted in 3 boxes is 3*3*3*3*3
= 3^5

if option (D)35 is 3^5 then D is the answer
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by Anurag@Gurome » Tue Nov 22, 2011 3:31 am
romitvsingh wrote:In how many ways can 5 letters be posted in 3 post boxes, if any number of letters can be posted in all of the three post boxes?

(A) 5 C 3
(B) 5 P 3
(C) 53
(D) 35
(E) 25
pls explain in detail
The first letter can be posted in any of the 3 post boxes.oSO, it has 3 choices.
In the same way, the 2nd, 3rd, 4th and 5th letter can each be posted in any of the 3 post boxes.
Therefore, the total number of ways the 5 letters can be posted in 3 boxes is 3 * 3 * 3 * 3 * 3
= 3^5
The correct answer is D.
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