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WE:Business Development (Energy and Utilities)
Re: Marisa has $40 more than Ben, and Ben has one-third as much
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05 Jul 2018, 01:36
Explanation
Translate the given information. Let M equal Marisa’s money and B equal Ben’s:
\(M = B + 40\)
\(B =\frac{1}{3} M\)
The question asks for B, so solve the second equation for M and substitute into the first equation:
\(3B = M\)
\(3B = B + 40\)
\(2B = 40\)
\(B = 20\)
Check the answer. If Ben has $20 and Marisa has $40 more than Ben, she has $60. It is true that Ben has one-third as much money as Marisa.