Question

Maria has written two numbers in her excercise copy such that the addition of 21 with the
first number gives twice of the second number. Again, addition of 12 with the second
number gives twice of the first number. Let us calculate and write the two numbers Maria
has written? ​

Answer 1

Answer:

Maria's first number was 15, and her second number was 18.

Step-by-step explanation:

Let x be the first number and y be the second number.

Now, according to the Question,

x + 21 = 2y

x = 2y - 21 ----- 1

Also,

y + 12 = 2x ------ 2

Substituting eq.1 in eq.2, we get,

y + 12 = 2(2y - 21)

y + 12 = 4y - 42

4y - y = 42 + 12

3y = 54

y = 54/3

y = 18

Putting y = 18 in eq.1 we get,

x = 2(18) - 21

x = 36 - 21

x = 15

Hence,

Maria's first number was 15, and her second number was 18.

Hope it helped and believing you understood it........All the best