There are 45 people in the school participating in the mathematics interest group, and 68 people in the computer interest group. There are 15 people who participate in both the mathematics interest group and the computer interest group. How many students participate in these two interest groups?
学校参加数学兴趣小组的有45人，参加计算机兴趣小组的有68人．既参加数学兴趣小组又参加计算机兴趣小组的有15人，参加这两个兴趣小组的同学共有多少人？
<gadget id="calculator">68 - 15</gadget>
<output>53</output>

<gadget id="calculator">45 + 53</gadget>
<output>98</output>

<result>98</result>