Integral Applications: Rate of Change

[olicoh]

Hey guys,
I was wondering if you could just check this problem for me (I put it in a Word Document and attached it to this post).

The problem, my work, and my attempted solution is included in it.

Thanks!

 

[eczeno]

looks correct.

 

[Mark44]

Very nicely formatted!

A couple of suggestions:
1) Include dt in your integral, like so
\int_0^{15}\left(\frac{40}{(2t + 1)^2}-60\right)dt
2) Write your answer as a sentence, not an equation, and include units.