Sports club

A sports club was purchasing new equipment. It bought three identical soccer balls and five identical volleyball balls, spending a total of 4,480 CZK. A soccer ball cost 320 CZK more than a volleyball. Determine how much the sports club would pay if it purchased four soccer balls and seven volleyball balls.

Final Answer:

x =  6120 Kc

Step-by-step explanation:

$$\begin{gathered} 3f+5v=4480 \\ f=320+v \\ 3\cdot f+5\cdot v=4480 \\ 3f+5v=4480 \\ f-v=320 \\ Row2-\frac{1}{3}\cdot Row1\to Row2 \\ -2.67v=-1173.33 \\ v=\frac{-1173.33333333}{-2.66666667}=440 \\ f=\frac{4480-5v}{3}=\frac{4480-5\cdot 440}{3}=760 \\ f=760 \\ v=440 \\ x=4\cdot f+7\cdot v=4\cdot 760+7\cdot 440=6120\text{Kc} \end{gathered}$$

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