To build a road, an engineering team repaired (3/8) kilometers in the first week, (2/5) kilometers in the second week, and (1/4) kilometers less than the sum of the previous two weeks in the third week , How many kilometers did you repair in the third week?
修一条路，某工程队第一周修了(3/8)千米，第二周修了(2/5)千米，第三周修的比前两周的总和少(1/4)千米，第三周修了多少千米？
<gadget id="calculator">3 / 8</gadget>
<output>3/8 = around 0.375</output>

<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(2/5) - (1/4)</gadget>
<output>3/20 = around 0.15</output>

<gadget id="calculator">(3/8) + (3/20)</gadget>
<output>21/40 = around 0.525</output>

<result>21/40 = around 0.525</result>