If a typist types a manuscript, if he types 20 pages a day, he can finish typing in 15 days. How many pages should be typed every day if it is to be typed in 12 days? (answer with ratio)
一位打字员打一本书稿，如果每天打20页，15天可以打完．若要12天打完，每天应打多少页？(用比例解答)
<gadget id="calculator">20 * 15</gadget>
<output>300</output>

<gadget id="calculator">300 / 12</gadget>
<output>25</output>

<result>25</result>