There are 40 students in the first class of the sixth grade. In the half-term quality inspection, the number of students who got excellent, good, passed and failed in mathematics were 20, 15, 3 and 2 respectively. What is the passing rate of mathematics in this class?
六年级一班有学生40人，在半期质量检测中，数学成绩得优、良、及格和不及格的人数分别是20人、15人、3人和2人，这个班数学及格率是多少．
<gadget id="calculator">20 + 15 + 3</gadget>
<output>38</output>

<gadget id="calculator">38 / 40</gadget>
<output>19/20 = around 0.95</output>

<gadget id="calculator">100 / 100</gadget>
<output>1</output>

<gadget id="calculator">(19/20) * 1</gadget>
<output>19/20 = around 0.95</output>

<result>19/20 = around 0.95</result>