Xiaojie did not take the language test in the class due to illness. The average score of the other students in his group was 92 points, and Xiaojie's score in the make-up exam was 72 points. After adding Xiaojie's scores, the average score of the group students was 90 points. How many people are there in their group?
小杰因病没有参加班上的语文测试，他们小组其他同学的平均成绩是92分，小杰补考成绩是72分，加上小杰的成绩后，小组同学的平均成绩是90分．他们小组共有多少人？
<gadget id="calculator">92 - 72</gadget>
<output>20</output>

<gadget id="calculator">92 - 90</gadget>
<output>2</output>

<gadget id="calculator">20 / 2</gadget>
<output>10</output>

<result>10</result>