A right triangle, the sum of the two sides is 35 cm, and their ratio is 3:4, what is the area of this right triangle?
一个直角三角形，两条直角边的和是35厘米，它们的比是3：4，这个直角三角形的面积是多少？
<gadget id="calculator">3 + 4</gadget>
<output>7</output>

<gadget id="calculator">3 / 7</gadget>
<output>3/7 = around 0.428571</output>

<gadget id="calculator">35 * (3/7)</gadget>
<output>15</output>

<gadget id="calculator">4 / 7</gadget>
<output>4/7 = around 0.571429</output>

<gadget id="calculator">35 * (4/7)</gadget>
<output>20</output>

<gadget id="calculator">20 / 2</gadget>
<output>10</output>

<gadget id="calculator">15 * 10</gadget>
<output>150</output>

<result>150</result>