There are five numbers arranged in a column, their average is 38, the average of the first three numbers is 35, and the average of the last three numbers is 40, find the third number.
有五个数排列成一列，它们的平均数是38，前三个数的平均数是35，后三个数的平均数是40，求第三个数．
<gadget id="calculator">35 * 3</gadget>
<output>105</output>

<gadget id="calculator">40 * 3</gadget>
<output>120</output>

<gadget id="calculator">38 * 5</gadget>
<output>190</output>

<gadget id="calculator">120 - 190</gadget>
<output>-70</output>

<gadget id="calculator">105 + (-70)</gadget>
<output>35</output>

<result>35</result>