A rectangle has a perimeter of 36 cm, a length of 10 cm, and a width of 10 cm.
一个长方形周长36厘米，长10厘米，宽是多少厘米．
<gadget id="calculator">36 / 2</gadget>
<output>18</output>

<gadget id="calculator">18 - 10</gadget>
<output>8</output>

<result>8</result>