Honghong's family raises 10 chickens, including 8 hens, which lay 1920 eggs a year. How many eggs does each hen lay per month on average?
红红家养了10只鸡，其中8只母鸡，一年共生蛋1920个，平均每只母鸡每月生蛋多少个？
<gadget id="calculator">1_920 / 8 / 12</gadget>
<output>20</output>

<result>20</result>