Students with more than 30 but less than 50 students form a circle, counting continuously from someone. If the same person reported "30" and "198", how many people are there in total?
由多于30人少于50人的学生围成一个圆圈，从某人开始连续报数．如果报"30"和"198"的是同一人时，请问一共有多少人？
<gadget id="calculator">3 * 2 * 7</gadget>
<output>42</output>

<result>42</result>