SOLUTION: John is three times his son's age. If the difference between their ages is 30, how old is the son. I think the problem is set up like 3n-n=30 If this is right, how do I solve it?

Question 435572: John is three times his son's age. If the difference between their ages is 30, how old is the son.
I think the problem is set up like 3n-n=30 If this is right, how do I solve it?
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
John is three times his son's age.
If the difference between their ages is 30, how old is the son.
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Equations:
j = 3s
j-s = 30
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Substitute for "j" and solve for "x":
3s-s = 30
2s = 30
s = 15 (The son's age now)
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Solve for "j":
j = 3s
j = 3*15 = 45 yrs old (John's age now)
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Cheers,
Stan H.
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