The school holds a sports meeting. There are 4 classes in each grade of the third, fourth and fifth grades, and each class selects 12 athletes to participate in the competition. How many athletes in grades 3, 4, and 5 participated in the competition?
学校开运动会，三、四、五年级每个年级有4个班，每个班选出12名运动员参加比赛．三、四、五年级一共有多少名运动员参加比赛？
<gadget id="calculator">12 * 4 * 3</gadget>
<output>144</output>

<result>144</result>