Math question?!? complex fractions! please help.?

Question

ok i have no idea how to do ym math homework. there are 5 questions but if someone explains the first to me it will probably be all that i need.:

In a dance class 2/7 of the men are married to 1/5 of the women. What fraction of the dance class is women.

i kinda had somthing goin but am completly confused. Please help somebody =]

Answer 1

let's set up a couple of variables m= men in the class and w=woman in the class. Also let us assume in this cass that everone that is married is only married to one person. so we can set up an eqaution:
2/7(m)=1/5(w)
or in words 2/7 of the men are equall in number to 1/5 of the women. To figure out what fraction of the class is female, we need a third varialble (c) for the entire class and to assume that there is no hermaphidites and a second equaition is apparnt:
m+w=c
now all we need to do is solve the two equaitions
2/7(m)=1/5(w)
5*(2/7)m=1/5(w)*5
10/7(m)=w
now subite
1m+(10/7(m))=c
17/7(m)=c
set c=1 for fractions of the class and solve
17/7(m)=1
m=7/17
7/17+w=1
w=10/17
the class has a mulitiple of 17 adults in it, 10/17 are women, and 7/17 are men

Answer 2

Well, let m be the number of men and w be the number of women. We know that 2/7 m = 1/5 w, so m = 7/10 w. The fraction of the dance class that is women is:

w/(m+w)

But m=7/10 w, so we have:

w/(7/10 w + w)
w/(17/10 w)

Canceling the w from both numerator and denominator:

1/(17/10)
10/17

So 10/17 of the class is women.

Answer 3

here 2/7men=1/5women
or 10men=7women

ratio of women=w/(m+w)=w/(w+7w/10)
=w(17w/10)=10/17