Subsequently 82599

The sweater was discounted by 20% in a fashion store and subsequently by 10% of the discounted price. After the discount, it costs CZK 1,080. How much was the sweater originally?

Correct answer:

a =  1500 Kc

Step-by-step explanation:

$$\begin{gathered} r_1=100\%-20\%=1-\frac{20}{100}=0.8 \\ {r}_2=100\%-10\%=1-\frac{10}{100}=0.9 \\ b=1080\text{Kc} \\ a\cdot r_1\cdot r_2=b \\ a=\frac{b}{r_1\cdot r_2}=\frac{1080}{0.8\cdot 0.9}=1500\text{Kc} \end{gathered}$$

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