Let the number of digits of 22005 be x and that of 52005 be y then the possible value of x+y=?

1 Answer
Aug 5, 2018

2005

Explanation:

Note that "number of digits" of n is essentially log10n+1

So:

x=log1022005+1=2005log102+1

y=log1052005+1

y=2005log105+1

y=2005(1log102)+1

y=2005(log102)+2006

y=2005log102+2006

So:

x+y=2005log1022005log102+2006=2005