"What would be the final temperature if you mixed a liter of 20 degrees C water with 2 liters of 40 degrees C water?" My teacher assigned us several problems like these without bothering to explain them. I have a hunch that they are embarrassingly simple to complete, but I know not how to find the solutions. The only equation we've been given to this point is Q = mcΔT. ANY help would be appreciated. Thanks in advance.