The average of the two numbers of A and B is 18, and B is three times that of A. What is B?
甲、乙两数的平均数是18，乙是甲的3倍，乙是多少．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

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

<gadget id="calculator">(1/2) + (3/2)</gadget>
<output>2</output>

<gadget id="calculator">18 / 2</gadget>
<output>9</output>

<gadget id="calculator">3 * 9</gadget>
<output>27</output>

<result>27</result>