Senior Class

[gmataspirenew]

In a certain senior class, 72% of the male students and 80% of the female students have applied to college.

What fraction of the students in the senior class are male.

 

1) There are 840 students in the senior class

2) 75% of the students in the senior class have applied to college.

[e.cartman]

Imo B.

With stmt 2, we can 0.72m+0.8f=0.75(m+f) from which it is possible to get the answer.

[gmataspirenew]

Thanks E.Cartmen.

 

But I am still not able to get how to calculate the required fraction from the

equation given by you.

 

Is there anything that I am missing? Can you please elaborate?

[e.cartman]

fraction needed is m/(m+f) = 1/(1+f/m)

Dividing the earlier equation throughout by m, you can get f/m and then substitute in the above.. but obviously we don't want to go that far for a ds question.

[supersuj]

Thanks E.Cartmen.

 

But I am still not able to get how to calculate the required fraction from the

equation given by you.

 

Is there anything that I am missing? Can you please elaborate?

 

 

Required fraction = m/(m+f)

 

0.72m + 0.8f = 0.75m + 0.75f

0.05f = 0.03m

f= 3/5*m = 0.6*m

 

so required fraction = m/(m+0.6m) = 1/1.6 = 5/8

 

Again, since this is a DS question, you dont need to do this bit of calculation once you arrive at the equation shown by e.cartman

 

Hope this helps!

[gmataspirenew]

Thanks a lot Supersuj and E.Cartman.