There are three classes in the sixth grade, the number of students in class one and class two and the number of people in the whole grade (9/14), the number of people in class two and class three and the number of people in the whole grade (19/28), it is known that there are students in class two 45 people, how many students are there in the third class?
六年级有三个班，一班、二班的人数和占全年级人数的(9/14)，二班、三班的人数和占全年级人数的(19/28)，已知二班有学生45人，三班有学生多少人？
<gadget id="calculator">9 / 14</gadget>
<output>9/14 = around 0.642857</output>

<gadget id="calculator">19 / 28</gadget>
<output>19/28 = around 0.678571</output>

<gadget id="calculator">(19/28) - 1</gadget>
<output>-9/28 = around -0.321429</output>

<gadget id="calculator">(9/14) + (-9/28)</gadget>
<output>9/28 = around 0.321429</output>

<gadget id="calculator">45 / (9/28)</gadget>
<output>140</output>

<gadget id="calculator">140 * (19/28)</gadget>
<output>95</output>

<gadget id="calculator">95 - 45</gadget>
<output>50</output>

<result>50</result>