On average, Guangming Primary School needs 43 barrels of mineral water per day. How many barrels of mineral water are needed for 3 weeks (calculated as 5 days per week)?
光明小学平均每天需要43桶矿泉水，3个星期(每个星期按5天计算)需要多少桶矿泉水？
<gadget id="calculator">43 * 5 * 3</gadget>
<output>645</output>

<result>645</result>