Verbal Reasoning - Arithmetic Reasoning - Discussion

Please explain clearly the logic any one.

Please explain each step clearly.

n=total no. of students.
r=rs. per student.
nr=96 i.e. r = 96/n

each students have to play 4rs. extra because 4 students did not turn up so:
(n-4)(r+4)=96
nr+4n-4r-16=96
n(96/n)+4n-4(96/n)-16=96
96+4n-4*96/n-16=96
4n*n-4*96-16n=0
n*n-4n-96=0
(n+8)(n-12)=0
n=12
n-4=8

@Sikandra. Very well explaned. Thanks so much.

Please explain clearly I didn't understand.

Sikander Kindly explain how it is possible.

4n*n-4*96-16n=0
n*n-4n-96=0
(n+8)(n-12)=0
n=12
n-4=8

Look 96..as we know 12*8=96, number of boys decrease by 4 burden increase by 4 each.

Just write (12-4)(8+4)=96 i.e. 8*12=96.
Hence who participated are.. 8.

Please explain clearly once again.

Very well @Neel....Shobha you can simply

80+4n -4 (96/n) = 96
4n - 4 (96/n) = 16.....divide by 1/4

Then as Neel explained (n+8)(n-12) = 96

Let us suppose that,
The no.of student are x & they decide to go to picnic & spend Rs. 96 in all students there for each student has to pay rupees.

96/x ( total student are x).

But 4 students did not turn up there for now each student has to pay 4 rupees extra.

96/(x-4) = 4+(96/x)

96/(x-4)+96/x = 4

96(x-x+4)/x(x-4) = 4

96 = x^2-4x

x^2-4x-96 = 0
x^2-12x+8x-96 = 0
x(x-12)+8(x-12) = 0
(x-12)(x+8) = 0
x = 12.

No. of students attend the picnic was x-4 = 8.
x-4 = 12-4.
x-4 = 8.