A box of Wanglaoji herbal tea is priced at 45 yuan, and there are 15 bottles in total. Xiaoli bought 4 bottles, how much does it cost?
一箱王老吉凉茶售价45元，共有15瓶，小丽买了4瓶，需要多少钱？
<gadget id="calculator">45 / 15</gadget>
<output>3</output>

<gadget id="calculator">3 * 4</gadget>
<output>12</output>

<result>12</result>