I'm not too sure either.
5(5) + 3(5) = 40 and
5(2) + 3 (10) = 40
If you can't think of anything maybe that'll help
If the ratio is 5:7 then the each part has a value of:
60/(5+7)=5 so from a total of 60
5:7 becomes 5*5:7*5 which is:
25:35
No . but she can buy 2 of the books but not all 3
