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Number of zeroes at the end of the number Î r^r where r varies from 1 to 25, is

(a) 50 (b) 49 (c) 49 (d) 100

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Soumyadeep Basu ·2014-03-30 10:26:10

The number of zeroes at the end=the exponent of 10 in the product=the exponent of (2X5) in the product. As the 2's outnumber the 5's, it will be sufficient to just count the number of 5's=(5+10+15+20+2X25)=100. (d).

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Soumak Roy okay ... ya this is the answer.
Upvote·0· Reply ·2014-03-31 09:23:28
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