Echoing Dr. Peterson and Jomo, the problem looks like
\(\displaystyle \int_{10}^{15}\frac{\pi U}{2U}e^{-\pi\left(\frac{U}{2U}\right)^2}du\)
I not sure if what looks like "U", a capital U, is supposed to be "u", the variable in "du". But, in any case \(\displaystyle \frac{U}{2U}= \frac{1}{2}\) so the integral is just \(\displaystyle \int_{10}^{15}\frac{\pi}{2}e^{-\frac{\pi}{2}}du=\)\(\displaystyle \frac{\pi}{2}e^{-\frac{\pi}{2}}\int_{10}^{15} du=\)\(\displaystyle \frac{\pi}{2}e^{-\frac{\pi}{2}}(15- 10)\).