Xiao Ming read 15 pages of the book in 5 days. According to this calculation, how many pages can he read in a month (30 days).
小明5天看了15页书，照这样计算，他一个月(30天)能看多少页书．
<gadget id="calculator">15 / 5</gadget>
<output>3</output>

<gadget id="calculator">3 * 30</gadget>
<output>90</output>

<result>90</result>