The school bought 5 volleyballs and 8 footballs for a total of 378 yuan. The price of each football is twice the price of volleyballs. How much is each volleyball?
学校买5个排球和8个足球共花了378元，每个足球的价格是排球价格的2倍，每个排球多少元？
<gadget id="calculator">8 * 2</gadget>
<output>16</output>

<gadget id="calculator">5 + 16</gadget>
<output>21</output>

<gadget id="calculator">378 / 21</gadget>
<output>18</output>

<result>18</result>