A: B: C = 2: 4: 7, and the average of the three numbers A, B, and C is 260, what is the largest number among them?
甲：乙：丙=2：4：7，且甲、乙、丙三个数的平均数是260，其中最大的数是多少．
<gadget id="calculator">2 + 4 + 7</gadget>
<output>13</output>

<gadget id="calculator">7 / 13</gadget>
<output>7/13 = around 0.538462</output>

<gadget id="calculator">260 * 3 * (7/13)</gadget>
<output>420</output>

<result>420</result>