The average of the three numbers is 75, and the ratio of the three numbers is 3:5:7. What is the largest number?
三个数的平均数是75，三个数的比是3：5：7，其中最大的数是多少？
<gadget id="calculator">3 + 5 + 7</gadget>
<output>15</output>

<gadget id="calculator">7 / 15</gadget>
<output>7/15 = around 0.466667</output>

<gadget id="calculator">75 * 3 * (7/15)</gadget>
<output>105</output>

<result>105</result>