The average of the four numbers is 88. If one number is changed to 88, the average of the four numbers is 100. So, what is the changed number?
四个数的平均数是88，现在将一个数改为88，则这四个数的平均数为100，那么，被改动的这个数是多少？
<gadget id="calculator">100 * 4</gadget>
<output>400</output>

<gadget id="calculator">88 * 4</gadget>
<output>352</output>

<gadget id="calculator">400 - 352</gadget>
<output>48</output>

<gadget id="calculator">88 - 48</gadget>
<output>40</output>

<result>40</result>