Tanvi94 wrote:
IR question from MBA.com
Guys please help with OA - Explaination
Lets list the variables to make this problem easier to keep track of:
F = % change of faculty
S = % change of students
R = Stu(1999) / Fac(1999)
R(2004) = Stu(2004) / Fac(2004)
Stu(1999) = 5500
We are asked to find:
1.) Fac(1999) = ?
2.) R(2004) = ?
1.)
R = Stu(1999) / Fac(1999)
Fac(1999) = Stu(1999) / R
Fac(1999) = 5500 / R2.) R(2004) = Stu(2004) / Fac(2004)
OR R(2004) = the previous Student / Faculty ratio times the change over the past 5 years.
The change is given: S, and F respectively.
Thus (100+S) / (100+f) NOTE: the 100 represents 100%, so 100% the ratio from 1999 +/- the change in the past 5 years (which is S and F)
R(2004) = R * (100+S) / (100+f)
The trick in this problem is the sign of the S and F. These variables should be added. Even though the problem states that the number of students is decreasing, while number of faculty is increasing, when you calculate out the rates, they should still be added. If the rate was negative, adding a negative rate is still subtracting it. Meanwhile if you subtracted the negative rate, it would flip the sign and mess up the calculation.