The students from class 5 and 1 went to visit the old revolutionary base area and spent 10 hours in total; the time spent on the road accounted for (1/5), the time for lunch and rest accounted for (3/10), and the rest was for sightseeing. What percentage of the total time does the tour take?
五1班学生去革命老区参观，共用去10时；其中路上用去的时间占(1/5)，吃午饭与休息时间共占(3/10)，剩下的是游览的时间．游览的时间占全部时间的几分之几？
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">3 / 10</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">1 - (1/5) - (3/10)</gadget>
<output>1/2 = around 0.5</output>

<result>1/2 = around 0.5</result>