There are 3 classes A, B and C for the fourth grade in a certain school. There are 100 students in Class A and Class B, 101 students in Class B and C, and 97 students in Class A and C. How many students are there in Class A?
某学校四年级有甲、乙丙3个班，甲班和乙班共有100人，乙班和丙班共有101人，甲班和丙班共有97人．甲班有学生多少人．
<gadget id="calculator">101 - 97</gadget>
<output>4</output>

<gadget id="calculator">100 + 4</gadget>
<output>104</output>

<gadget id="calculator">104 / 2</gadget>
<output>52</output>

<gadget id="calculator">100 - 52</gadget>
<output>48</output>

<result>48</result>