"Six One" Children's Day, the brigade counselors bought prizes for outstanding young pioneers. I originally planned to buy 6 notebooks, and the total cost is 72 yuan. Now I plan to buy 15 notebooks like this, how much will it cost?
"六一"儿童节，大队辅导员为优秀少先队员买奖品．原计划买6本笔记本，共需72元钱，现在准备买这样的笔记本15本，需要多少元钱．
<gadget id="calculator">72 / 6</gadget>
<output>12</output>

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

<result>180</result>