In order to improve the comprehensive quality of teachers and enrich their spare time life, Unlimited Learning Source School organizes a typing competition for teachers. The competition requires typing the same article. Teacher Li can type 100 characters per minute, which can be finished in 80 minutes. Teacher Wang can type less than Teacher Li per minute. 20 characters. How many minutes does it take Mr. Wang to finish typing? (answer in two ways)
为了教师综合素质，丰富业余生活，无限学源学校组织教师打字比赛活动，比赛要求打同一篇文章，李老师每分钟打100个字，80分钟可以打完，王老师每分钟比李老师少打20个字．王老师打完需要多少分钟？(用两种方法解答)
<gadget id="calculator">100 - 20</gadget>
<output>80</output>

<gadget id="calculator">80 / 80</gadget>
<output>1</output>

<gadget id="calculator">100 * 1 * 80</gadget>
<output>8_000</output>

<gadget id="calculator">8_000 / 80</gadget>
<output>100</output>

<result>100</result>