Let there be m males and f females. We need to find m/(m+f)

1) Clearly not enough

2) clearly not enough

1+2

0.33m + 0.20f = 0.25(m+f)

This gives us 8m - 5f = 0, which gives us the ratio between males and females. This is sufficient to calculate m/(m+f)

(C)

Right, I kiiinda see it, and was somewhat on that track, but it's still not clear in my head.

Can anyone else chime in with a more thorough answer, and maybe a strategy for how to deal with these types?

I think that part of what made this difficult for me was that I found the wording confusing.

joannabanana wrote:Right, I kiiinda see it, and was somewhat on that track, but it's still not clear in my head.

Can anyone else chime in with a more thorough answer, and maybe a strategy for how to deal with these types?

I think that part of what made this difficult for me was that I found the wording confusing.

Ok, heres another shot...

Let there be a total of m males, and f females in the graduating class. Thus, total number who graduated = m+f
We need to find the fraction of males from this, which means m/(m+f)

Now, lets look at 1

33% males and 20% females = (33/100)m + (20/200)f

Now, lets look at 2

25% of total students transferred from another colleged => (25/100)(m+f) transferred from another college.

Thus

0.33m + 0.20f = 0.25(m+f)

Multiply both sides by 100

33m + 20f = 25m + 25f
=> 8m= 5f => m = (5/8)f

Now, lets see if this is enough to find m/(m+f)

= (5/8)f/[(5/8)f + f]

= (5/8)f/(13/8)f = 5/13

Hence, the ratio is 5/13.

Hope that's a bit more clear

I also got confused by the wording... I assumed some of the students did not graduate from the class and hence picked E...