Question

Pupil's of 10th standard of a school had arranged for a function at a total cost of Rs.1,000 which was to be shared equally among them. Since 10 of them failed to join the function each of them had to pay Rs.5 more. Find the number of pupils in the class?

Answer 1

let number of pupil are x and each take money is y

a/c to question ,
1000/x = y --------------------(1)

again ,
1000/(x-10)= y + 5 -----------(2)

subtracting equation (1) from (2)
1000{ 1/(x-10) - 1/ x } = 5
10000/(x^2-10x) = 5
x^2 -10 x -2000= 0
use quadratic formula ,
x={ 10 +_root (100+8000)}/2
= (10 +_90)/2
=50 , -40

so number of pupil are 50

Answer 2

Answer:

the number of pupils in the class is 50