Xingfu Primary School visited the "Shenzhou VI" spaceship scientific and technological achievements exhibition. 45 people participated in the third grade, three times the number of participants in the fourth grade, four times the number of participants in the sixth 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，三年级参加了45人，四年级参加的人数是三年级的3倍，六年级参加的人数是四年级的4倍，六年级有多少人参加？
<gadget id="calculator">45 * 3 * 4</gadget>
<output>540</output>

<result>540</result>