If 2/7 of the men in the class are engaged to 1/5 of the women, what fraction of the class consists of women ?

Question

It's geometry homework. I need the answer ASAP. Thanks

Answer 1

In the class you have 1/5 of the women that are married to guys in the class and 4/5 that are not.

Let's take an arbitrary number of 2 women (married) and 8 (unmarried).

That means we need 2 men to be married. Therefore the total number of men would be n. We know 2/7 of n = 2, so n = 7

That would put our ratios as 7 men and 10 women.

The ratio of women in the class is 10 women to 17 total students, or 10/17.

Answer 2

Assuming that each man is engaged to one woman--a reasonable assumption, I think--then 2/7 the number of men in the class is the same number as 1/5 the number of women. Multiply the fractions by 7/2 and you find that the number of men is equal to 7/10 the number of men. So the total number of students is equal to the number of women, plus 7/10 the number of women, or 17/10 the number of women.

Now if the number of students is 17/10 times the number of women, then the number of women must be 10/17 times the number of students, so 10/17 of the class are women. That makes the other 7/17 men.

To test the answer, plug your original data back in. 2/7 of the men is 2/7 of 7/17 of the class, which is 2/17 of the class. 1/5 of the women is 1/5 of 10/17 of the class, which is also 2/17 of the class, so the answer checks out.

10/17 of the class consists of women.

Answer 3

Assuming that engagement consists of one man and one woman:
T is the total number of people in the class. M is the number of men W is the number of women. M + W = T

W/T is the fraction of men in the class, what we're looking for.

What we're given is that 2M / 7 = W / 5
multiplying both sides by 35 so everything is an integer
10M = 7

back to the original: M + W = T
then multiply by 10
10M + 10W = 10T
substitute in 10M = 7W
7W + 10W = 10T
17W = 10T
W / T = 10 / 17

The simplest way for this to work is to have 7 men and 10 women in the class. You can check that 2/7 of the men and 1/5 of the women figures out to 2 of each, so the answer makes sense.

Answer 4

rewrite as equations:

2/7 * Men = 1/5 * Women (assuming each only engaged to 1 person)

Class = Men + Women

you want: Women / Class

men = (1/5)/(2/7) *Women

so Class = 7/10*Women + Women = 17/10 * women

women / class = 10/17

Answer 5

10/17

Answer 6

I get 10/17

you have (2/7)*m = (1/5)*w ==> m = (7/10)*w

ratio : w / (w+m) = w/ ((17/10)*w) ==> 10/17

Answer 7

1/5/(1/5+2/7)=1/5*35/17
fraction of women=7/17

Answer 8

Sorry, but this has nothing to do with Geometry.

In any event the problem as stated has no solution.