How many of the three-digit numbers whose sum is equal to 19 are multiples of 11?
在各位数字之和等于19的三位数中，有多少个是11的倍数．
<gadget id="calculator">19 - 11</gadget>
<output>8</output>

<gadget id="calculator">8 / 2</gadget>
<output>4</output>

<result>4</result>