Three workers in the orchard collect apples, and they collect 210 kilograms of apples in 3.5 hours. On average, how many kilograms of apples do they collect per hour?
果园里3个工人收苹果，3.5小时共收了210千克，平均每人每个小时收了多少千克苹果？
<gadget id="calculator">210 / 3 / 3.5</gadget>
<output>20</output>

<result>20</result>