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
borrowed.

How many girls were there at the YHS meeting?

(In reply to

I agree by broll)

15 books per boy(b), 20 books per girl(g). **says who?**

15b+20g=305, **WRONG 305 should include parents' part too**

**hint: **

** let g denote the number of girls , b - boys, c=b+g number of chldren and p=c/3 parents**

SOLVE IN INTEGERS

** 17g+12(c-g)+9c/3=305 **

which reduces to** 5g+15c=305**

** i.e. g+3c=61 **where c>g and 3 divides c

**\.............g=7 c=18 p=6.................../**

why not edit your post??