10 pens are packed in a box, 24 boxes are packed in a box, and each pen costs 9 yuan. How much does it cost to buy a box of pens?
10支钢笔装一盒，24盒装一箱，每支钢笔9元钱，买一箱钢笔要多少元钱？
<gadget id="calculator">10 * 24 * 9</gadget>
<output>2_160</output>

<result>2_160</result>