A certain area was hit by a disaster. After the disaster, a section of (3/4) kilometers long seawall was to be rebuilt. (1/3) was repaired on the first day, and (2/5) was repaired on the second day. How many kilometers of seawall were built in total in two days?
某地区受灾，灾后要重建一段长(3/4)千米的海堤，第一天修了(1/3)，第二天修了(2/5)，两天一共修海堤多少千米？
<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

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

<gadget id="calculator">(1/3) + (2/5)</gadget>
<output>11/15 = around 0.733333</output>

<gadget id="calculator">(3/4) * (11/15)</gadget>
<output>11/20 = around 0.55</output>

<result>11/20 = around 0.55</result>