There are less than 50 students in a class. In a test, (1/3) students get excellent, (1/2) students get good, and (1/7) students pass. Then, how many people fail ．
某班学生不到50人，在一次测验中，有(1/3)的学生得优，(1/2)的学生得良，(1/7)的学生及格，那么，有多少人不及格．
<gadget id="calculator">2 * 3 * 7</gadget>
<output>42</output>

<gadget id="calculator">42 - 14 - 21 - 6</gadget>
<output>1</output>

<result>1</result>