"I Love Invention" is priced at 7.50 yuan per copy. There are 51 people in Class 51, and each person buys a copy, how much is the total cost.
《我爱发明》每本定价是7.50元．五1班共有51人，每人买一本，共要多少元．
<gadget id="calculator">7.5 * 51</gadget>
<output>382.5</output>

<result>382.5</result>