The number of absentees in Class 1 today is 1/8 of the number of people present, and 4 people asked for sick leave later, so the number of absentees is 25% of the number of people present. How many people are there in this class?
六1班今天缺勤人数是出勤人数的(1/8)，后又有4人请病假，于是缺勤人数是出勤人数的25%．这个班共有多少人？
<gadget id="calculator">1 + 4</gadget>
<output>5</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 + 8</gadget>
<output>9</output>

<gadget id="calculator">1 / 9</gadget>
<output>1/9 = around 0.111111</output>

<gadget id="calculator">(1/5) - (1/9)</gadget>
<output>4/45 = around 0.088889</output>

<gadget id="calculator">4 / (4/45)</gadget>
<output>45</output>

<result>45</result>