A problem by Anika .
Level
pending
What is the sum of the digits of the decimal form of the product ?
7
5
10
13
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1 solution
2^1999 X 5^2001 =
2^1999 X 5^1999 X 5^2
making it equal to 25 X 10^1999 , a number with the digits "25" followed by 1999 zeros. The sum of the digits in the decimal form would be 2+5=7 thus making the answer 7