Answered this myself as I wrote it. 1. The problem statement, all variables and given/known data Eight bricks, each 6.0 cm thick with a mass of 1.5 kg, lie flat on a table. How much work is required to stack them one on top of another? hbrick = 0.060 m m = 1.5 kg 2. Relevant equations W = Fd Fg = m*g 3. The attempt at a solution I tried the following, and was correct. Please read the fourth point for my question. Fg = 1.5*9.8 = 14.7 N Wt = W1+W2+W3+W4+W5+W6+W7+W8 Wt = 14.7*0 + 14.7*.06 + . . . + 14.7*0.42 = 25 J 4. My question The answer to the question goes a little something exactly like this: Where did that 3.5 come from? 7 bricks lifted divided by 2? Oh . . . Probably. Yeah. Averages and what not. Writing this helped. Might as well post it.