A cuboid oil barrel has a bottom area of 25 square decimeters and a height of 1.5 meters. If such a barrel of oil is filled into a bottle with a capacity of 50 ml, how many bottles are needed to fill it up?
一种长方体油桶，它的底面积是25平方分米，高是1.5米，把这样的一桶油注人容积为50毫升的瓶子里，要多少个瓶子才能装完？
<gadget id="calculator">1_000 / 50</gadget>
<output>20</output>

<gadget id="calculator">25 * 1.5 * 10 * 20</gadget>
<output>7_500</output>

<result>7_500</result>