Question 1150389

Twelve years ago my father was twice as old as I was, and three years ago our combined age was 108. How old is my father now?
<pre>Let father's age be F, and my age, M
Then we get: F - 12 = 2(M - 12)____F - 12 = 2M - 24____F - 2M = - 12 ---- eq (i)
Also, since their ages summed to 108, 3 years ago, then now, their ages sum to 108 + 2(3) = 108 + 6 = 114
We then get: F + M = 114____M = 114 - F ------ eq (ii)
F - 2(114 - F) = - 12 ----- Substituting 114 - F for M in eq (i)
F - 228 + 2F = - 12
3F = 216
F, or father's age is: {{{highlight_green(matrix(1,3, 216/3, "=", 72))}}}
That's ALL!!