1. The problem statement, all variables and given/known data Xi ~ U(80,120) find the E[X1+X2+...+Xn]=? 2. Relevant equations 3. The attempt at a solution Why can't I do this?: E[X1+X2+...+Xn]=n*E[X1] and just find the expected value? Is that because the distribution changes as we increase the number of elements of uniforms we sum? Is there some trick here? I found something called "Irwin–Hall distribution"... is this it?