An engineering team paved a section of railway. The original plan was to pave 3.2 kilometers per day, but the actual pavement was 25% more than the original plan every day. It took 12 days to actually complete this section of railway. How many days did you plan to take to finish?
一支工程队铺一段铁路，原计划每天铺3.2千米，实际每天比原计划多铺25%，实际铺完这段铁路用了12天．原计划用多少天才能铺完？
<gadget id="calculator">25 / 100</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 + (1/4)</gadget>
<output>5/4 = around 1.25</output>

<gadget id="calculator">12 / 3.2</gadget>
<output>3.75</output>

<gadget id="calculator">3.2 * (5/4) * 3.75</gadget>
<output>15</output>

<result>15</result>