Question

what is the answer of this question ​

Answer 1

Age of son is 3

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Answer 2

Let the present age of son = x years

Let the present age of father = y years

3 years ago,

Son's age = (x - 3) years

Father's age = (y - 3)years

According to question

7(x - 3) = (y - 3)

7x - 21 = y - 3

7x - y = - 3 + 21

7x - y = 18 (Equation 1)

3 years hence,

Son's age = (x + 3) years

Father's age = (y + 3) years

According to question

4(x + 3) = (y + 3)

4x + 12 = y + 3

4x - y = 3 - 12

4x - y = -9 (Equation 2)

Subtracting Equation 2 from Equation 1

7x - 4x - y + y = 18 + 9

3x = 27

x = $\dfrac{27}{3}$

x = 9

Hence, present age of the son is 9 years.