31 exercise books and 49 pencils are distributed to the students on average. As a result, there is one less exercise book and one more pencil. What is the maximum number of these students?
把31本练习本，49枝铅笔，平均分给学生，结果练习本少一本，铅笔多一枝，这些学生最多有多少个．
<gadget id="calculator">2 * 2 * 2 * 2</gadget>
<output>16</output>

<result>16</result>