InterviewSolution
 Saved Bookmarks
    				| 1. | 
                                    There are some students in the two examination halls A and B. To make the number of students equal in each hall, 10 students are sent from A to B but, if 20 students are sent from B to A, the number of students in A becomes double the number of students in B, then find the number of students in the both halls. | 
                            
| 
                                   
Answer» Let the number of students in halls A and B are x and y, respectively. Now, by given condition, `" " x-10=y+10` `rArr " " x-y=20 " " ...(i)` and `" " (x+20)=2(y-20)` `rArr " " x-2y=-60 " " ...(ii)` On subtracting Eq. (ii) from Eq. (i) , we get `(x-y)-(x-2y)=20+60` `x-y-x+2y=80 rArr y = 80` On putting y = 80 in Eq. (i), we get x-80=20`rArr`x=100 and `" "`y=80 Hence, 100 students are in hall A and 80 students are in hall B.  | 
                            |