SOLUTION: * Please help me. I couldn't figure out how to write the linear equation of this problem. thank you. John’s father is 5 times older than John and John is twice as old as his sis

Algebra ->  Customizable Word Problem Solvers  -> Age -> SOLUTION: * Please help me. I couldn't figure out how to write the linear equation of this problem. thank you. John’s father is 5 times older than John and John is twice as old as his sis      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 502953: * Please help me. I couldn't figure out how to write the linear equation of this problem. thank you.
John’s father is 5 times older than John and John is twice as old as his sister
Alice. In two years time, the sum of their ages will be 60 . How old is John
now?
Answer by jrb1965(16) About Me  (Show Source):
You can put this solution on YOUR website!
F = Father
J = John
A = Alice
Now J = 2A, and F = 5J = 5(2A) = 10A
In two years (F + 2) + (J + 2) + (A + 2) = 60, so F + J + A = 54
Substitute all in terms of A
10A + 2A + A = 54, 13A = 54, so A = 54/13 (check your numbers, they usually make these come out in even years)
F = 41.54
J = 8.31
A = 4.15