There are 15 students who can be divided into 3 groups to play games. Now there are 9 groups of students who are playing games. How many people are playing games?
有15个同学可以分成3组做游戏，现在有9组同学在做游戏，做游戏的一共多少人？
<gadget id="calculator">15 / 3</gadget>
<output>5</output>

<gadget id="calculator">5 * 9</gadget>
<output>45</output>

<result>45</result>