The length of a rectangle is 2.2 decimeters, the circumference is 84 centimeters, what is the width in centimeters? (solution by equation)
一个长方形的长是2.2分米，周长是84厘米，宽是多少厘米？(用方程解)
<gadget id="calculator">22 * 2</gadget>
<output>44</output>

<gadget id="calculator">84 - 44</gadget>
<output>40</output>

<gadget id="calculator">40 / 2</gadget>
<output>20</output>

<result>20</result>