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Math Help - integers

  1. #1
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    integers

    The integers from 1 to 25 are multiplied together. How many zeros does the result end in?

    (A) 2 (B) 3 (C) 4 (D) 5 (E) 6
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  2. #2
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    Quote Originally Posted by sri340 View Post
    The integers from 1 to 25 are multiplied together. How many zeros does the result end in?

    (A) 2 (B) 3 (C) 4 (D) 5 (E) 6

    Hi sri,

    The product is 25 factorial which is 1.5511200 E25. 18 more zeros would fill it out


    bjh
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  3. #3
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    25! = 15511210043330985984000000 actually, but you only need to find the power of 10 in the product to know how many zeros are at the end. Remember that 1,2,5, and 10 are the factors of 10 and count the number of times a multiple of ten appears in the product.
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