Xingfu Primary School visited the "Shenzhou VI" spaceship scientific and technological achievements exhibition. 25 people in the fourth grade participated, twice as many people in the fifth grade as the fourth grade, three times as many people in the sixth grade as the fifth grade, how many people in the sixth grade participated ?
幸福小学参观"神舟六号"飞船科技成果展览，四年级参加了25人，五年级参加的人数是四年级的2倍，六年级参加的人数是五年级的3倍，六年级有多少人参加？
<gadget id="calculator">25 * 2 * 3</gadget>
<output>150</output>

<result>150</result>