The average math score of a certain class is 91.5 points. During the re-examination, it was found that a classmate's 98 points were mistakenly calculated as 89 points when calculating the grades. After recalculation, the average math score of the whole class was 91.7 points. Then this class has how many students
某班同学数学考试平均分为91.5分，复查时发现，计算成绩时将一名同学的98分误作89分计算了，经重新计算后，全班数学平均分为91.7分，那么这个班有多少学生？
<gadget id="calculator">98 - 89</gadget>
<output>9</output>

<gadget id="calculator">91.7 - 91.5</gadget>
<output>0.2</output>

<gadget id="calculator">9 / 0.2</gadget>
<output>45</output>

<result>45</result>