Question 1036311
ray is 15 years older than sam and sam is 12 years younger than bert. Their ages total 42 years. how old are they all 
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Equations:
r = s + 15
s = b-12
r + s = b = 42
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Substitute for "r" and for "b" and solve for "s"::
s+15 + s + s+12 = 42
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3s = 42-27
3s = 15
sam = 5 yrs
ray = s+15 = 20 yrs
bert = s+12 = 17 yrs
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Cheers,
Stan H.
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