The average of the four numbers A, B, C, and D is 38, the average of A, B is 42, the average of B, C, and D is 36, what is B?
A、B、C、D四个数的平均数是38，A、B的平均数是42，B、C、D的平均数是36，B是多少．
<gadget id="calculator">42 * 2</gadget>
<output>84</output>

<gadget id="calculator">36 * 3</gadget>
<output>108</output>

<gadget id="calculator">84 + 108</gadget>
<output>192</output>

<gadget id="calculator">38 * 4</gadget>
<output>152</output>

<gadget id="calculator">192 - 152</gadget>
<output>40</output>

<result>40</result>