The ratio of the sides of a right triangle is 3:4:5, and the sum of the two sides is 280 cm. What is the length of the hypotenuse of this triangle in cm?
一个直角三角形的三边的比是3：4：5，两条直角边之和是280厘米，这个三角形斜边的长度是多少厘米？
<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">280 * (3/7)</gadget>
<output>120</output>

<gadget id="calculator">120 / 3</gadget>
<output>40</output>

<gadget id="calculator">40 * 5</gadget>
<output>200</output>

<result>200</result>