The ratio of A, B, and C is 3:4:5. The average of these three numbers is 48. What is the number of B?
甲、乙、丙三个数的比是3：4：5，这三个数的平均数是48，乙数是多少
<gadget id="calculator">48 * 3</gadget>
<output>144</output>

<gadget id="calculator">3 + 4 + 5</gadget>
<output>12</output>

<gadget id="calculator">4 / 12</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">144 * (1/3)</gadget>
<output>48</output>

<result>48</result>