Wang Fang reads "Selected Compositions for Primary School Students" and plans to read 15 pages a day, which can be finished in 24 days. Due to the intense study, she actually only reads 12 pages a day. How many days can she finish this "Selected Compositions for Primary School Students"? (Solve with ratio)
王芳看一本《小学生作文选》，计划每天看15页，24天可以看完，由于学习比较紧张，她实际每天才看12页，多少天可以把这本《小学生作文选》看完？(用比例解)
<gadget id="calculator">15 * 24</gadget>
<output>360</output>

<gadget id="calculator">360 / 12</gadget>
<output>30</output>

<result>30</result>