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.

2 answers

I also don't quite see how that problem ties in with common factoring, etc.

Unless the teacher is looking for multiples of 5 feet that go into 75

each computer needs 30 inches plus 30 inches to one side, for a total of 60 inches or 5 feet.
So starting with 30 inches on one side of the room we could mark off 5 feet at a time until we reach 25 feet.
so we have 5,10,15,20,25
but that would mean that the first computer would have to be right against the wall.
a rather confusing question for a grade 5
find the prime fractorization of each number .20