One (Xinhua Dictionary) is 3 centimeters thick, and 5 (Xinhua Dictionary) are stacked together, how many centimeters are they thick?
一本(新华字典)厚3厘米，5本(新华字典)摞在一起，厚多少厘米．
<gadget id="calculator">3 * 5</gadget>
<output>15</output>

<result>15</result>