Grandpa Wang raised 200 chickens, 150 ducks, and 50 geese. If a fan-shaped statistical chart is made to show the number of chickens, what is the central angle of the fan-shaped circle in degrees?
王爷爷养了200只鸡，150只鸭，50只鹅，如果制成扇形统计图，表示鸡的只数，扇形圆心角是多少°度．
<gadget id="calculator">200 + 150 + 50</gadget>
<output>400</output>

<gadget id="calculator">200 / 400</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">360 * (1/2)</gadget>
<output>180</output>

<result>180</result>