Find sum of digits when (10^50) - 50 is written as whole #

Hello, quick homework question...

If (10^50) - 50 is written as a whole number, find the sum of it's digits.

Okay, I got 6 initially, but my teacher said that it was a very big number.

If the problem were to find the sum of the digits of say 10[sup:j9sh1w67]5[/sup:j9sh1w67]-50 it would look like this...

100000
-00050
099950

We see that the number of zeros in the first line is the same as the exponent of 10 in the original problem and the number of places in the first line is one more than the size of the exponent.
We see that our answer has the same number of places as the exponent.
We see that the number of nines is two less than the size of the exponent.
We see that there is one five and one zero.
Therefore the answer to this made up problem is 3 X 9 + 5 + 0 = 32.
Can you do the same for your problem without having to write it out longhand?