Carcass wrote:
In  a  certain  class, \(\frac{1}{5}\) of the  boys  are  shorter  than  the  shortest  girl  in  the  class, and  \(\frac{1}{3}\) of the  girls  are  taller than  the  tallest  boy  in  the  class.  If there  are  16  students  in the class  and  no two  people have the same height, what  percent of the students are taller than the shortest girl  and  shorter than the tallest boy?
A. 25%
B. 50%
C. 62.5%
D. 66.7%
E. 75%
NOTE: I'm probably over explaining things here, but I want the solution to be absolutely clear. 
GIVEN: There are 16 students and 1/5 of them are boys. 
This means the number of boys 
must be a multiple of 5. 
There are 3 possible cases: 
i) 5 boys and 11 girls
ii) 10 boys and 6 girls   iii) 15 boys and 1 girl
GIVEN: There are 16 students and 1/3 of them are girls. 
This means the number of girls 
must be a multiple of 3. 
When we check the three possible cases above, we see that only one case (
case ii) is such that the number of girls is divisible by 3. 
So we now know that there are 
10 boys and 6 girlsLet 
A, B, C, D, E, F represent the heights of the 6 girls arranged in ASCENDING order
Let 
Q, R, S, T, U, V, W, X, Y, Z represent the heights of the 10 boys arranged in ASCENDING order
1/5 of the boys are  shorter  than  the  shortest  girl  in  the  class1/5 of 10 = 2
So, 2 boys are  shorter  than  the  shortest  girl  in  the  class
We have: 
Q, R, A [ these 3 heights must be arranged in ascending order] 1/3 of the  girls  are  taller than  the  tallest  boy  in  the  class1/3 of 2 = 2
So, 2 girls are taller than the tallest boy in the class
We have: 
Z, E, F [ these 3 heights must be arranged in ascending order]NOTE: The remaining students must lie BETWEEN 
A and 
Z, however there is no way to determine the relationships between each boy and each girl within this range.
So one possible configuration is as follows: 
Q, R, A, 
S, T, U, V, W, X, Y, 
B, C, D, Z, E, FWhat percent of the students are taller than the shortest girl and shorter than the tallest boy?Shortest girl is 
A and the tallest boy is 
ZAs we can see from the above diagram, there are 10 such students
10/16 = 5/8 = 62.5% 
Answer: C
Cheers,
Brent