The base of a triangle is 3m long. If the base is extended by 1m, the area of the triangle increases by 1.2m**2. What is the area of the original triangle in m**2?
一个三角的底长3m，如果底延长1m，那么三角形的面积就增加1.2m**2．原来三角形的面积是多少m**2？
<gadget id="calculator">2 / 1</gadget>
<output>2</output>

<gadget id="calculator">1.2 * 2</gadget>
<output>2.4</output>

<gadget id="calculator">2.4 / 2</gadget>
<output>1.2</output>

<gadget id="calculator">3 * 1.2</gadget>
<output>3.6</output>

<result>3.6</result>