Uncle Zhang's chicken farm hatched 460 chicks in 21 days. There are still 90 eggs that have not yet hatched. How many eggs are used to hatch chicks in Uncle Zhang's chicken farm?
张叔叔的养鸡场21天孵出460只小鸡．还有90个没有孵出来，张叔叔的养鸡场孵小鸡一共用了多少个鸡蛋．
<gadget id="calculator">460 + 90</gadget>
<output>550</output>

<result>550</result>