A chicken farm raises 800 geese and 970 ducks. The number of chickens is 150 less than the total number of geese and ducks. How many chickens are raised?
一个养鸡场养鹅800只，养鸭970只，养鸡的只数比鹅、鸭的总数少150只，养鸡多少只？
<gadget id="calculator">800 + 970</gadget>
<output>1_770</output>

<gadget id="calculator">1_770 - 150</gadget>
<output>1_620</output>

<result>1_620</result>