SOLUTION: Andrew is now one quarter of his father's age. In 4 years he wil be one third of his father's age. How old are Andrew and his father now? I need help on setting up the equation an

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Question 773211: Andrew is now one quarter of his father's age. In 4 years he wil be one third of his father's age. How old are Andrew and his father now?
I need help on setting up the equation and then solving.
Let A=Andrew's age now.
Let F=The fathers age now.
I tried A=1/4*F.
Then the second equation I wrote down is A+4=1/3*F+4.
I dont't know what to do next.
Answer by John10(297) (Show Source):
You can put this solution on YOUR website!
Hint: Substitute the first equation into the second equation for A:
(1/4)F + 4 = (1/3)(F + 4)
(1/4)F + 4 = (1/3)(F) + 4/3
(1/4)F - (1/3)F = -4 + 4/3
(-1/12)F = -8/3
F/12 = 8/3
F = (8/3)(12) = 32
A = (1/4)F = 32/4 = 8
Andrew is 8 years of age
Father is 32 years of age
Hope it helps!
John10