The perimeter of a right triangle is 48 cm. The ratio of the lengths of the three sides of this triangle is 3:4:5. What is the length of the longest side of this triangle in cm?
一个直角三角形的周长是48厘米，这个三角形的三条边长度之比是3：4：5，这个三角形最长的这条边的长度是多少厘米？
<gadget id="calculator">3 + 4 + 5</gadget>
<output>12</output>

<gadget id="calculator">5 / 12</gadget>
<output>5/12 = around 0.416667</output>

<gadget id="calculator">48 * (5/12)</gadget>
<output>20</output>

<result>20</result>