There are 15 boys and 10 girls in Miss Li's class. She wants to group all the students so that each group has the same number of boys and girls as the other groups. What is the greatest number of groups she can have?

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Answer 1 · 2018-04-23T12:39:39

#5# groups, each one having #3# boys and #2# girls

The most groups you can have would be #5#.

You have to find the factors of #10 and 15#, and see which one is the greatest common factor.

Once you see that the only two factors they share are #1 and 5#, you choose the bigger one as the answer.

Answer 2 · 2018-04-23T12:51:34

There will be #5# groups with #3# boys and #2# girls in each group.

If she tries to make #15# groups with one boy in each, there are not enough girls to have #1# in each group.

If she has #10# groups with #1# girl in each, she will not be able to divide the boys evenly.

The ratio is

boys : girls

#15" " : " "10" "# which simplifies to

#3" ": " "2#

She can therefore divide the class into groups with #5# students in each group.

There will be #5# groups.

#5# is the highest common factor of #15 and 10#