If the sum of 2007 is 9, how many four-digit numbers have the sum of 11?
2007的数字和是9，那么数字和是11的四位数有多少个．
<gadget id="calculator">10 + 1</gadget>
<output>11</output>

<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<gadget id="calculator">11 * 5</gadget>
<output>55</output>

<gadget id="calculator">9 + 1</gadget>
<output>10</output>

<gadget id="calculator">9 / 2</gadget>
<output>9/2 = around 4.5</output>

<gadget id="calculator">10 * (9/2)</gadget>
<output>45</output>

<gadget id="calculator">8 + 1</gadget>
<output>9</output>

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

<gadget id="calculator">9 * 4</gadget>
<output>36</output>

<gadget id="calculator">7 + 1</gadget>
<output>8</output>

<gadget id="calculator">7 / 2</gadget>
<output>7/2 = around 3.5</output>

<gadget id="calculator">8 * (7/2)</gadget>
<output>28</output>

<gadget id="calculator">6 + 1</gadget>
<output>7</output>

<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<gadget id="calculator">7 * 3</gadget>
<output>21</output>

<gadget id="calculator">5 + 1</gadget>
<output>6</output>

<gadget id="calculator">5 / 2</gadget>
<output>5/2 = around 2.5</output>

<gadget id="calculator">6 * (5/2)</gadget>
<output>15</output>

<gadget id="calculator">4 + 1</gadget>
<output>5</output>

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

<gadget id="calculator">5 * 2</gadget>
<output>10</output>

<gadget id="calculator">3 + 1</gadget>
<output>4</output>

<gadget id="calculator">3 / 2</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">4 * (3/2)</gadget>
<output>6</output>

<gadget id="calculator">55 + 45 + 36 + 28 + 21 + 15 + 10 + 6</gadget>
<output>216</output>

<result>216</result>