The ratio of the three numbers A, B and C is 2:3:4, the average of the three numbers is 108, what is the middle number of these three numbers
甲、乙、丙三个数的比是2：3：4，三个数的平均数是108，求这三个数的中间数是多少
<gadget id="calculator">2 + 3 + 4</gadget>
<output>9</output>

<gadget id="calculator">3 / 9</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">108 * 3 * (1/3)</gadget>
<output>108</output>

<result>108</result>