Afreight train starts from los angeles and heads for chicago at 40 mph. two hours later, a passenger train leaves the same station for chicago traveling 60 mph. how long before the passenger train over takes the freight train?

I'm going to assume that they are on parallel tracks, and not the same track.

60x=40(x+2)

60x=40x+80

20x=80

x=4

You can check the work I've provided by filling in the answer for x into the initial question.

ʕ·ᴥ·ʔ

Okay, so for a square you take the square root to find the length of an individual side, so 100 is 10 and 64 is 8.
a prism is length x width x height. so you take 8x10x2, which is 160. that is one layer, so you multiply it by 2. so the total volume is 320 inches cubed.