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600-700 digits problem

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by rtaha2412 » Fri Oct 22, 2010 11:47 am
I had trouble interpreting and then solving this problem. Please advise

What is the least number of digits (including repetitions) needed to express [m]10[square_root]100[/square_root][/m] in decimal notation?

a 4
b 100
c 101
d 1000
e 1001
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Source: — Problem Solving |

by shovan85 » Fri Oct 22, 2010 12:02 pm
Hi rtaha2412,

I think your Q is not properly formatted so its does not seem clear. However I think below is the proper Question.

What is the least number of digits (including repetitions) needed to express 10^100 in decimal notation?

As per Interpretation, try to visualize what has been asked. The question is asking total number of digits when 10^100 will have.

See 10^1 = 10 have 2 digits
10^2 = 100 have 3 digits
10^3 = 1000 have 4 digits.....

So in general 10^n has (n+1) integer.

So put n=100 then (n+1) = 101

IMO C
If the problem is Easy Respect it, if the problem is tough Attack it
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