There are 6 numbers, their average is 25, the average of the first 3 numbers is 21, and the average of the last 4 numbers is 32. So what is the value of the third number?
现有6个数，它们的平均数是25，前3个数的平均数是21，后4个数的平均数是32．那么第3个数的值是多少．
<gadget id="calculator">21 * 3</gadget>
<output>63</output>

<gadget id="calculator">32 * 4</gadget>
<output>128</output>

<gadget id="calculator">25 * 6</gadget>
<output>150</output>

<gadget id="calculator">128 - 150</gadget>
<output>-22</output>

<gadget id="calculator">63 + (-22)</gadget>
<output>41</output>

<result>41</result>