Aptitude Hack#142(15-07-19)

Question:

In the classroom, there are some benches and some students. if one student sits per bench then 9 more benches are required. If two students sit per bench there are no students on 3 benches. find the number of students in the class.

A) 16
B) 20
C) 22
D) 24

Answer: D) 24.

Explanation:

Let no of students be S.
And Let no of Benches be B.

So,(One student per bench)
=> S/1 =B+9   ------(1)

And (Two students per bench)
=>  S/2=B-3.
=> S=2(B-3)
=> S=2B-6. ------(2)

From 1 and 2 we get.
=> B+9=2B-6
=> B=9+6
=> B=15.
 And S=B+9 =15+9=24.