Data Sufficiency Problem..

[odod]

Hello,

Got another one...


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

A) 4
B) 100
C) 101
D) 1000
e) 1001.

Answer is C.

Any idea how to get this? I'm not even sure where to start...

[yalanand]

Its pretty easy

We know 10^1 = 10 (2 digits)
10^2=100(3 digits) in general

10^n=(n+1) digits

Hence 10^100 = 100+1=101 digits