A rectangular vegetable field is 15 meters wide, and its length is 1.8 times its width. What is the perimeter of this vegetable field?
一个长方形菜地宽15米，长是宽的1.8倍，这块菜地的周长是多少？
<gadget id="calculator">15 * 1.8</gadget>
<output>27</output>

<gadget id="calculator">15 + 27</gadget>
<output>42</output>

<gadget id="calculator">42 * 2</gadget>
<output>84</output>

<result>84</result>