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# Need some help here. Thank you.

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A box contained some \$5 notes. David took $${1\over 3}{}{}$$ of the notes and another 2 more

notes to buy a wallet. Then he took 50% of the remaining notes and 2 more notes to

buy a watch. Finally he took $${1 \over 2}{}{}$$ of what was left and another 2 notes to buy a book.

In the end, he had 7 pieces of notes left in the box. How much money was in the box

at first?

Sep 7, 2021

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The box starts with x  notes.   (the money value is never important)

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He takes     $$\frac{x}{3}+2 = \frac{x+6}{3}$$

and leaves  $$\frac{2x}{3}-2=\frac{2x-6}{3}\\$$

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from the ones left

he takes  $$\frac{1}{2}*\frac{2x-6}{3}+2=\frac{x-3}{3}+\frac{6}{3}=\frac{x+3}{3}\\$$

and leaves   $$\frac{x-3}{3}-\frac{6}{3}=\frac{x-9}{3}$$

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from the ones left

he takes  $$\frac{1}{2}*\frac{x-9}{3}+2$$

and leaves ...

AND you should be able to take it from there

Sep 9, 2021