SOLUTION: If last year I was twice as old as my son and this year you can put my age backwards for my sons age how old are we?

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Question 1094316: If last year I was twice as old as my son and this year you can put my age backwards for my sons age how old are we?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
If last year I was twice as old as my son
f -1 = 2(s-1)
f - 1 = 2s - 2
f = 2s - 2 + 1
f = 2s - 1
and this year you can put my age backwards for my sons age
write the fathers age as 10x+y, where x=the 10s' and y=the units
then
Write the son's age reversing the digits: 10y+x
:
how old are we?
In the first simplified equation replace:
f = (10a+y), and s = (10y+x)
10x + y = 2(10y+x) - 1
10x + y = 20y + 2x - 1
10x - 2x = 20y - y - 1
8x = 19y - 1
x = %28%2819y-1%29%29%2F8
looking at the table of this equation we find only integer solution is when y=3
x = %28%2819%283%29-1%29%29%2F8
x = %28%2857-1%29%29%2F8
x = 56%2F8
x = 7
Therefore
Father's age is 73 and Son's age is 37
:
:
We can check this, one year ago
son was 36 and father was 72, twice the son's age