In order to celebrate the National Day, the students of Class 6 and 2 have to make 150 small flags, and they have already done (4/5), how many flags are left?
为举行庆国庆活动，六二班学生要做150面小旗，已经做了(4/5)，还有多少面没有做？
<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">150 * (1/5)</gadget>
<output>30</output>

<result>30</result>