There is a piece of colored silk 10 meters long, and (3/4) of it is made into colorful flags. (4/5) of these flags are used to decorate the classroom. How many meters of colored silk are used to decorate the colorful flags in the classroom?
有一条10米长的彩绸，其中的(3/4)做成了彩旗．这些彩旗的(4/5)用来装饰教室．装饰教室的彩旗用去彩绸多少米？
<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">10 * (3/4) * (4/5)</gadget>
<output>6</output>

<result>6</result>