Uncle Zhang, a professional pig farmer, has 5 pig pens in total, and each pig pen has 8 pigs. Feeding 800 kg of feed a day, how much feed does each pig feed on average?
养猪专业户张大爷家共有5个猪圈，每个猪圈有8头猪．一天喂800千克饲料，平均每头猪喂多少饲料？
<gadget id="calculator">5 * 8</gadget>
<output>40</output>

<gadget id="calculator">800 / 40</gadget>
<output>20</output>

<result>20</result>