http://img269.imageshack.us/img269/1556/32975927.jpg

I'm interpreting it as saying that you take .15 of the new accumulated value for each increase in a degree C... So Is(total) = Is1 + Is1*.15 + Is2*.15 where Is2=Is1*.15 and do that 100 times... not sure how though.

Thanks

 

It's simply .....

Is[@25C]*(1.15)^100 = 10^(-14)*1.174*10^6=1.174*10^(-8)

 

You may be missing the simple formula for doing it. You are not trying to calculate the sum of the terms, only the final term. The increase is (1+rate)^n. The final answer is: Is(total) = Is(initial)(1+0.15)^100

John