Use 120 cm long iron wire to form a right triangle. The ratio of the three sides of this triangle is 3:4:5. What is the area of this right triangle in square centimeters?
用120厘米长铁丝围成一个直角三角形，这个三角形三条边的比是3：4：5．这个直角三角形的面积是多少平方厘米？
<gadget id="calculator">3 + 4 + 5</gadget>
<output>12</output>

<gadget id="calculator">3 / 12</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">120 * (1/4)</gadget>
<output>30</output>

<gadget id="calculator">4 / 12</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">120 * (1/3)</gadget>
<output>40</output>

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

<gadget id="calculator">30 * 20</gadget>
<output>600</output>

<result>600</result>