The experimental primary school needs to build a playground. In order to complete the project 3 days ahead of schedule, the original work efficiency must be increased by 12%. How many days was originally planned to complete the project.
实验小学要修一个操场．为了使工程能提前3天完成，须把原定工效提高12%．原计划完成这一工程用多少天．
<gadget id="calculator">12 / 100</gadget>
<output>3/25 = around 0.12</output>

<gadget id="calculator">(3/25) * 3</gadget>
<output>9/25 = around 0.36</output>

<gadget id="calculator">3 + (9/25)</gadget>
<output>84/25 = around 3.36</output>

<gadget id="calculator">(3/25) - 1</gadget>
<output>-22/25 = around -0.88</output>

<gadget id="calculator">1 + (-22/25)</gadget>
<output>3/25 = around 0.12</output>

<gadget id="calculator">(84/25) / (3/25)</gadget>
<output>28</output>

<result>28</result>