It is known that the formula for calculating the perimeter of a rectangle is c=(a+b)x2, when a=20cm and b=16cm, what is the perimeter in centimeters?
已知长方形的周长计算公式是c=(a+b)x2，当a=20厘米、b=16厘米时，周长是多少厘米？
<gadget id="calculator">20 + 16</gadget>
<output>36</output>

<gadget id="calculator">36 * 2</gadget>
<output>72</output>

<result>72</result>