Question

Age of mom 10 yrs ago was thrice the daughter age, ten years hence mother age will be twice the daughter sum of their presemt ages

Answer 1

Let present age of mother be x
and present age of daughter be y
$10 \: \: years \: \: ago \\ x - 10 = 3(y - 10) \\ x - 3y = - 20 - - - (1) \\10 \: \: years \: \: after \\ x + 10 = 2(y + 10) \\ x - 2y = 10 - - - (2) \\ (2) - (1) \: \: gives \\ y = 30 \\ from \: \: (1) \\ x = 3 \times 30 - 20 = 70$