Verbal Reasoning - Arithmetic Reasoning - Discussion

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.

Please explain each step clearly. I cannot understand any step.

4 that did not turn up x(x). Total of students == total money used, hence.

4x = 96 = 24.

But since each added 4rs to cover up = 4rsx4 (not turned up) = 16.

Subtract. 24 total of students - 16 = 8.

4(x-4x) = 96.
4x-16x = 96.
-12x = 96.
x = 8.

You explained very simple and it clear my doubt, thank you @Ashok.

An unconventional way of solving it, but it's only good if you have multiple choice answers in front of you:

Step 1: 96 (total amount)/8 (Answer A) = $12 (individual contribution).

Step 2: 8 (the # of people attending the picnic) + 4 (who have left) = 12.

Step 3: 96 (total amount)/12 (initial group) = $8.

Step 4: $8 (individual contribution for the group of 12)-$12 (individual contribution for the group of 8) = -4.

Step 5: 12*8 = 96 and 8*12 = 96.