Teacher Wang went to the stationery store and bought 3 boxes of pens, 5 pens in each box, and 12 yuan each. How much should Teacher Wang pay?
王老师到文具店买了3盒钢笔，每盒5枝，每枝12元，王老师应付多少元？
<gadget id="calculator">5 * 3</gadget>
<output>15</output>

<gadget id="calculator">12 * 15</gadget>
<output>180</output>

<result>180</result>