book of fairy tales has 180 pages in total, and Xiaohong read 60 pages in the first 4 days. Based on this calculation, how many days will it take to finish reading this book?
一本童话故事书共有180页，小红前4天看了60页．照这样计算，这本书一共需要多少天看完？
<gadget id="calculator">60 / 4</gadget>
<output>15</output>

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

<result>12</result>