There are 21 female students and 18 male students in the handicraft group of the school. The number of people in the painting group is three times that of the manual group. How many people are there in the painting group?
学校手工组有女同学21人，男同学18人．绘画组的人数是手工组的3倍，绘画组有多少人？
<gadget id="calculator">42 * 3</gadget>
<output>126</output>

<result>126</result>