A 1,200-meter road is built. (1/4) is repaired on the first day, and (2/5) is repaired on the second day. After two days of repairing, how many meters are left unrepaired?
修一条1200米的公路，第一天修了(1/4)，第二天修了(2/5)，修了两天后还有多少米没有修？
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

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

<gadget id="calculator">(1/4) + (2/5)</gadget>
<output>13/20 = around 0.65</output>

<gadget id="calculator">1_200 * (13/20)</gadget>
<output>780</output>

<gadget id="calculator">1_200 - 780</gadget>
<output>420</output>

<result>420</result>