man practiced shooting, and his shooting rate was 20% when he was wearing glasses, and 0% when he was not wearing glasses. If he misses the target after shooting 5 times in a row, find the probability that he wears glasses.
某男子练射击，在有戴眼镜的情况命中率为20%，没戴眼镜则命中率为0%．其在连续射击5次后都未命中目标，求其戴了眼镜的概率．
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

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

<gadget id="calculator">(4/5) ** 5</gadget>
<output>1_024/3_125 = around 0.32768</output>

<gadget id="calculator">(1_024/3_125) + 1</gadget>
<output>4_149/3_125 = around 1.32768</output>

<gadget id="calculator">(1_024/3_125) / (4_149/3_125)</gadget>
<output>1_024/4_149 = around 0.246806</output>

<result>1_024/4_149 = around 0.246806</result>