Question 875058
a group of students are on tour the total fare is Rs 1200 and this is to be shared equally among the students. if two more students join the tour each will pay Rs 20 less. find the original # of students?
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let x=original number of students
x+2=new number number of students
..
{{{1200/x-1200/(x+2)=20}}}
1200(x+2)-1200x=20x(x+2)
1200x+2400-1200x=20x^2+40x
20x^2+40x-2400=0
x^2+2x-120=0
(x-10)(x+12)=0
x=-12(reject)
or 
x=10
original number of students=10