Question 102631
Mona earns three times as much as an actuary as she does as a writer.  Her total income is $40,000 more than her brother.  He makes half as much as Mona does as an actuary.  What is Mona's salary as an actuary?
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Let brother's salary be "b" ; Let Mona's salary be "m".
EQUATIONS:
m = b + 40000
b = (1/2)m
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Substitute to get:
m = (1/2)m + 40000
(1/2)m = 40000
m = $80000 (Mona's salary)
Substitute to solve for "b":
b = (1/2)80000
b = $40000 (brother's salary)
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Cheers,
Stan H.