What is the quotient of the sum of all three-digit numbers composed of 3, 4, and 5 divided by the sum of these three numbers?
由3、4、5所组成的所有三位数的和除以这三个数的和，商是多少．
<gadget id="calculator">345 + 354 + 435 + 453 + 534 + 543</gadget>
<output>2_664</output>

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

<gadget id="calculator">2_664 / 12</gadget>
<output>222</output>

<result>222</result>