At a meeting of the Young Historical Society (YHS) in a local library the number of children present
was three times the number of parents.
At this meeting, each boy borrowed 12 books from the
library, each girl borrowed 17 books and each parent borrowed 9 books.
In total 305 books were
How many girls were there at the YHS meeting?
15 books per boy(b), 20 books per girl(g).
15b+20g=305, so 3b+4g=61. But also b+g=3 parents (p)
Substituting: 9p+g=61, and p=6, g=7, because if, say, p=5, then g= 16, and 16*20= 320, more than the given number of books.
So there were 7 girls at the YHS meeting.
What if the the number of children present was four times the number of parents?
Posted by broll
on 2018-02-12 22:04:32