initial budget=2000

initial no. of students= x

final no. of students= x-5

intial money given by each student= y

final money given by each student= y+20

so equation will be,

xy=2000 ..........(1)

(x-5)(y+20)=2000..................(2)

(x-5)(2000+20x)/x=2000

2000x-10000+20x^2-100x=2000x

20x^2-100x-10000=0

x^2-5x-500=0........(4)

Find x=?

then the rest procedure is very simple!!!!!!!!!!

Thankyou!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!11111111

5 student attend the picnic . 200 rupees each student paid .

please post some tough questions next time.

we have let x= no of student

y=money by each

then, xy=2000

and also , (x-5)(y+20)=2000

on simplifying we get

xy+20x-5y-100=xy

putting y=2000/x

we get  x^2-5x-500=0

then x=25 or -20

since -20 cannot be the no of student so x=25

20 students attended the picnic

each paid rs 100

let the no of students be ''x''

let the amount spent be ''y''

according to question,

x.y=2000   ..............(1)

since five students failed to attend =(x-5)

since the cost increased by rs.20=(y+20)

now the equation (1) becomes

(x-5)(y+20)=2000

xy+20x-5y-100=2000

20x-5y-100=0    [from (1)]

dividing throughout by 5,we get

4x-y-20=0

substitute the value of y from equation (1), i.e.,  y=2000/x

you will get equation like this

x.x-5x-500=0

when u solve this u wil get,x=25.

and final answer is 25 students attended the picnic