Xiao Ling read a story book, and read 20 pages in 4 days. According to this calculation, I read it for another 5 days. How many pages have I read in total? (Use ratio to solve).
小玲读一本故事书，4天读了20页．照这样计算，又读了5天，一共读了多少页？(用比列解)．
<gadget id="calculator">20 / 4</gadget>
<output>5</output>

<gadget id="calculator">5 * 4</gadget>
<output>20</output>

<gadget id="calculator">5 * 5</gadget>
<output>25</output>

<gadget id="calculator">20 + 25</gadget>
<output>45</output>

<result>45</result>