The ratio of the three numbers A, B, and C is 3:4:5. Given that C is 9.5, what is the sum of the numbers A and B?
甲、乙、丙三个数的比是3：4：5，已知丙是9.5，甲、乙两数之和是多少．
<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">9.5 / (5/12)</gadget>
<output>22.8</output>

<gadget id="calculator">22.8 - 9.5</gadget>
<output>13.3</output>

<result>13.3</result>