There are 250 chickens in a farm, the number of ducks is three times that of chickens, and the number of geese is 70 less than the total number of chickens and ducks. How many geese do you raise?
某饲养场中养鸡250只，养鸭的只数是鸡的3倍，鹅的只数比鸡、鸭总只数少70只．养鹅多少只？
<gadget id="calculator">250 * 3</gadget>
<output>750</output>

<gadget id="calculator">250 - 70</gadget>
<output>180</output>

<gadget id="calculator">750 + 180</gadget>
<output>930</output>

<result>930</result>