In the party's mass line education practice activities, Mr. Li made a plan to complete a few words of reading notes. He completed the plan (1/4) in the first month, completed 15,000 words in the second month, completed (1/8) the plan in the third month, and just completed the planned task in three months. How many words of reading notes is Mr. Li's plan?
在党的群众路线教育实践活动中，李老师制定了完成若干字读书笔记的计划．他第一个月完成了计划的(1/4)，第二个月完成了15000字，第三个月完成了计划的(1/8)，三个月刚好完成了计划的任务．李老师的计划是多少字的读书笔记？
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 / 8</gadget>
<output>1/8 = around 0.125</output>

<gadget id="calculator">(1/4) + (1/8)</gadget>
<output>3/8 = around 0.375</output>

<gadget id="calculator">1 - (3/8)</gadget>
<output>5/8 = around 0.625</output>

<gadget id="calculator">15_000 / (5/8)</gadget>
<output>24_000</output>

<result>24_000</result>