Question

please answer this question ​

Answer 1

let the present age of son be x and father be y..

According to question,

y-3 = 7(x-3). and y+3 = 4(x+3)

y-3 = 7x -21. and y+3 = 4x + 12....(ii)

y = 7x -18....(i)

putting (i) in (ii), we get

(7x - 18) + 3 = 4x + 12

7x -15 = 4x + 12

3x = 27

so x = 9

so y = 7(9) - 18

= 63 - 18

y = 45

Answer 2

$\text{Present age of father = x}\\\text{Present age of son = y}\\\\\\\textbf{\underline{3 Years Earlier}}\\\\\text{Age of father = x-3}\\\text{Age of son= y-3}\\\\\text{Father is 7 times old as his son}\\\\\implies x-3=7(y-3)\\\\x=7y-18---[1]\\\\\\\textbf{\underline{3 Years Hence}}\\\\\text{Age of father = x+3}\\\text{Age of son= y+3}\\\\\text{Age of father is 4 times that of his son}}\\\\\implies x+3=4(y+3)\\\\x=4y+9---[2]\\\\\\\\\text{from [1] and [2]}\\\\7y-18=4y+9\\\\3y=27\\\\\boxed{\bold{y=9}}$

$x=4y+9\\\\x=4(9)+9\\\\\boxed{\bold{x=45}}$