math
posted by Darcie .
my daughter is doing homework using greatest common factor, greatest common divisor, and prime factorization. She has this problem: Computers in the research room of the history museum are 30 wide, 30 inches apart and at either end of a row 30 inches from the wall. How many computers can fit across a room that is 25 feet wide?
I can do the problem in my head but I don't know how to explain it to her or to tell her how to show her work. What is the teacher looking for on how to solve this problem? I've tried to read the chapter over and over again and it doesn't make sense to me whatsoever.

30 inches = 2.5 ft
25 ft2.5 ft = 22.5 ft left after space is left for 2.5 ft space at the far wall
Each computer/space unit takes 60 inches or 5 feet.
so
22.5/5 = 4.5 computer/space units
So only four will fit if you leave 30 inches from the wall at each end. If you only have the 30 inch space at one wall, you can get five in. 
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