The school brings in 20 bundles of books, each bundle has 6 packs, and each pack has 15 books. How many books are there in total?
学校运进20捆书，每捆有6包，每包有15本，一共有书多少本？
<gadget id="calculator">20 * 6 * 15</gadget>
<output>1_800</output>

<result>1_800</result>