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Melanie spent half of her allowance going to the movies. She washed the family car and earned nine dollars. What is her weekly allowance if she ended with eighteen dollars ? please help show work

User Cuonglm
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1 Answer

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Melanie's weekly allowance is $18

Step-by-step explanation:

let Melanie allowance = b

She spent half of it on movies = 1/2 × b = b/2

Amount left after removing movie cost = b - b/2

Then earned an additional $9 = (b - b/2) + 9

The total money Melanie has now = $18

b - b/2 + 9 = 18


\begin{gathered} (b)/(1)-(b)/(2)+9=18 \\ (b)/(1)-(b)/(2)=18-9 \\ (2b-b)/(2)=9 \end{gathered}
\begin{gathered} (b)/(2)=\text{ 9} \\ b\text{ = 9(2)b } \\ b\text{ = 18} \end{gathered}

Hence, Melanie's weekly allowance is $18

User Yaroslav Dukal
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