The store shipped 200 red and blue sweaters in total, and the number of red sweaters was 20 times more than the number of blue sweaters. How many blue sweaters were shipped? (column equation solution)
商店运来红、蓝毛衣一共200件，其中红毛衣的件数比蓝毛衣的件数的2倍多20件．运来的蓝毛衣有多少件？(列方程解答)
<gadget id="calculator">200 - 20</gadget>
<output>180</output>

<gadget id="calculator">1 + 2</gadget>
<output>3</output>

<gadget id="calculator">180 / 3</gadget>
<output>60</output>

<result>60</result>