A barrel of pure water is 4.5 yuan. Our school used 85 barrels this month. How much does it cost to buy these pure water?
一桶纯净水4.5元，这个月我们学校用了85桶，买这些纯净水要花多少钱？
<gadget id="calculator">4.5 * 85</gadget>
<output>382.5</output>

<result>382.5</result>