There is a bottle of 80% alcohol solution, pour out (1/2) and fill it up with water, shake it well and then pour it out (1/4), fill it up with water and pour it out (1/10), add Full of water, what is the concentration at this time? (column solution)
有一瓶浓度为80%的酒精溶液，倒出(1/2)后用水加满，摇匀后再倒出(1/4)，再加满水后再倒出(1/10)，再加满水，此时浓度多少？(列式解答)
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

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

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (1/4)</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">1 - (1/10)</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">8 * (1/2) * (3/4) * (9/10)</gadget>
<output>27/10 = around 2.7</output>

<gadget id="calculator">(27/10) / 10</gadget>
<output>27/100 = around 0.27</output>

<gadget id="calculator">100 / 100</gadget>
<output>1</output>

<gadget id="calculator">(27/100) * 1</gadget>
<output>27/100 = around 0.27</output>

<result>27/100 = around 0.27</result>