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 Question from Sindy, a student: Brandon went shopping & spent 1/4 of his money on shoes & 1/5 of the remainder on a new wallet. He then spent $\$60$on a pair of jeans. If he had$\$60$ left, how much did Brandon start with?

Hi Sindy,

Both problems you sent us I would call "working backwards" problems. For this problem I see 4 steps.

Step Action Value before
4 Count what's left $\$60$At step 4 he counted his money and he had$\$60.$ At step 3 he bought a pair of jeans for $\$60$and what he had left was$\$60$ so at step 3 he had $\$120.$Step Action Value before 1 Buy shoes 2 Buy wallet 3 Buy jeans$\$120$
4 Count what's left $\$60$At step 2 he bought a wallet with 1/5 of the money he had at this point. He was left with$\$120$ so 4/5 of the money he had at this point was $\$120.$Since$\large \frac{120}{4} \normalsize = 30$he spent$\$30$ on the wallet. Thus, before he bought the wallet he had $\$120 + \$30 = \$150.$Step Action Value before 1 Buy shoes 2 Buy wallet$\$150$
3 Buy jeans $\$120$4 Count what's left$\$60$

How much did he have before he bought the shoes? Check your answer by working forward.

Now try the second problem you sent us.

Penny

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