Mr. Zhang has to correct 52 compositions, and 20 of them have been corrected. If 8 articles are corrected every hour, how many hours will it take to complete the correction?
张老师要批改52篇作文，已经改了20篇．如果每小时改8篇，还要多少小时才可以批改完？
<gadget id="calculator">52 - 20</gadget>
<output>32</output>

<gadget id="calculator">32 / 8</gadget>
<output>4</output>

<result>4</result>