A refrigerator factory produces a total of 378 refrigerators in 3 weeks. How many refrigerators does the factory produce on average every day?
某电冰箱厂3个星期共生产378台电冰箱，该厂平均每天生产多少台电冰箱？
<gadget id="calculator">3 * 7</gadget>
<output>21</output>

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

<result>18</result>