ten years from now, A will be twice as old as B.Five years ago,A was three times as old as B.Whasst are the presnt ages of A and B?

Question

 algebra

Answer 1

Let A and B be the present ages of A and B respectively

 

A + 10 = 2(B + 10)   ; A + 10 = 2B + 20  ; A - 2B = 10    (1)

 

A - 5 = 3(B - 5)       ; A - 5 = 3B - 15      ; A - 3B = -10    (2)

 

(1) - (2) = 0 + B = 20   Hence B = 20 years

 

from (1) A - 2*20 = 10  ;         A = 50 years