Question

There are two examination rooms a and b if 10 students are sent from a to b,then the number of students in each room is the same .If 20 candidates are sent form b to a ,then the number of students in a is double the number of students in b.The number of students in room a is

Answer 1

Option C


Let the number of students in rooms A and B be xand y respectively.

Then, x - 10 = y + 10   =>   x - y = 20 .... (i)

     and x + 20 = 2(y - 20)    =>  x - 2y = -60 .... (ii)

Solving (i) and (ii) we get: x = 100 , y = 80.

The required answer A = 100.