five. The students in Class 8 tied up the collected waste products with a 4-meter-long rope. (4/5) of it was used up. How many meters are left?
五．八班的学生用一条长4米的绳子捆扎收聚的废品，用去了它的(4/5)，还剩下多少米？
<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">1 - (4/5)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">4 * (1/5)</gadget>
<output>4/5 = around 0.8</output>

<result>4/5 = around 0.8</result>