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Smart Puzzle

our planet earthSmart Puzzle - 28 September

Assume there are approximately 5,000,000,000 (5 billion) people on Earth. What would you estimate to be the result, if you multiply together the number of fingers on every person's left-hands? (For the purposes of this exercise, thumbs count as fingers, for five fingers per hand.) If you cannot estimate the number then try to guess how long the number would be ?

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  1. 25,000,000,000 easy

  2. 25 billion it's so easy

    1. that would be if you *added* them all.

      Multiplying would be 5^5,000,000,000 (assuming you are only multiplying those who actually have 5 fingers - safe assumption, since we're only counting 5 of the 7 billion people in the world). This would be the same as 10^log(5)*5,000,000,000 which is a number with roughly 3.5 billion digits

  3. According to WolframAlpha:
    5 to the power 5,000,000,000
    is roughly
    9 with 3,494,850,022 zeros behind it.

  4. There can be atleast one man without hands on the earth, making the answer ZERO!!!(X*0=0)