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Number of Digits in the answer

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Source: — Problem Solving |

by Anurag@Gurome » Sat Jan 28, 2012 12:09 am
xtremecoder007 wrote:The number of digits in 4^11 * 5^25?
(4^11)*(5^25) = (2^22)*(5^25) = (2^22)*(5^22)*(5^3) = [(2*5)^22]*(5^3) = (10^22)*(5^3) = (125)*(10^22)

Hence, the number is nothing but 125 followed by 22 zeroes.

Hence, number of digits in (4^11)*(5^25) is (3 + 22) = 25
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by tomada » Sat Jan 28, 2012 12:47 pm
Fantastic explanation!

Anurag@Gurome wrote:
xtremecoder007 wrote:The number of digits in 4^11 * 5^25?
(4^11)*(5^25) = (2^22)*(5^25) = (2^22)*(5^22)*(5^3) = [(2*5)^22]*(5^3) = (10^22)*(5^3) = (125)*(10^22)

Hence, the number is nothing but 125 followed by 22 zeroes.

Hence, number of digits in (4^11)*(5^25) is (3 + 22) = 25
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