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.

Explanation

To solve the problem, we will set up a system of equations based on the information given in the question.

### Step 1: Define the variables
Let:
- \( X \) = number of students in hall A
- \( Y \) = number of students in hall B

### Step 2: Set up the first equation
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