Sports club

A sports club was purchasing new equipment. It bought three identical soccer balls and five identical volleyball balls. It spent a total of 4480 CZK on the balls, with the soccer ball being 320 CZK more expensive than the 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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