Cauliflower sales

Miss Cabbage sells vegetables in the market. Yesterday, she offered two types of cauliflower - a large one for 25 CZK and a small one for 15 CZK. In the morning, she sold 8 boxes of 20 heads of cauliflower and thus earned 3,270 CZK. How many large and how many small cauliflowers did she sell?

Final Answer:

a =  87
b =  73

Step-by-step explanation:

$$\begin{gathered} 25a+15b=3270 \\ a+b=8\cdot 20 \\ 25a+15(8\cdot 20-a)=3270 \\ 25\cdot a+15\cdot (8\cdot 20-a)=3270 \\ 10a=870 \\ a=\frac{870}{10}=87 \\ a=87 \end{gathered}$$

$b=8\cdot 20-a=8\cdot 20-87=73$

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