Question 694781
ten years ago,arun's father was four times older than his son.after ten years, the father will be twice older son. the present age of arun.
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Equatiion:
f-10 = 4(s-10)
f+10 = 2(s+10)
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Rearrange:
f - 4s = -30
f - 2s =  10
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Subtract and solve for "s":
2s = 40
s = 20 yrs (son's age now)
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Solve for "f":
f = 2s+10
f = 40+10
f = 50 yrs (father's age now)
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Cheers,
Stan H.