A professional household raises 500 ducks, and the number of chickens raised is 120 less than three times that of ducks. How many more chickens are raised than ducks?
饲养专业户养了500只鸭，养的鸡比鸭的3倍少120只．养的鸡比鸭多多少只？
<gadget id="calculator">500 * 3</gadget>
<output>1_500</output>

<gadget id="calculator">1_500 - 120 - 500</gadget>
<output>880</output>

<result>880</result>