In a math test with a full score of 100, Zhang Ming took the first place in the class. He found that if his own grades were not counted, the average score of the class changed from 91 to 90.7. How many students are there at most in this class?
在一次满分为100分的数学考试中，张明考了全班第一名．他发现如果不算自己的成绩，全班平均分就由91分变成了90.7分．请问这个班最多有多少名同学？
<gadget id="calculator">100 - 90.7</gadget>
<output>9.3</output>

<gadget id="calculator">91 - 90.7</gadget>
<output>0.3</output>

<gadget id="calculator">9.3 / 0.3</gadget>
<output>31</output>

<result>31</result>