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Thanks Margaret. I understand now. Suppose the original price of the item is $\$p,$ in your example $\$p = \$100,$ and the sale price is $\$s,$ in your example $\$s = \$70.$ Suppose also that the employee price is $\$e,$ in your example $\$e = \$25.$ You know $\$s$ and you want to determine $\$p$ so that you can calculate $\$e.$ Since the sale is 30% off the relationship between $\$p$ and $\$s$ is that $\$s$ is 70% of $\$p$ or \[s = 0.70 \times p.\] Thus \[p = \frac{s}{0.70}.\] Since employees get a 75% discount, $\$e$ is 25% of $\$p,$ and hence \[e = 0.25 \times p.\] Putting the two expressions together gives \[e = 0.25 \times \frac{s}{0.70} = \frac{0.25}{0.70} \times p = \frac{25}{70} \times p\] which simplifies to \[e = \frac{5}{14} \times p.\] I hope this is what you are looking for. Penny




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