(2/3)+(2/9)+(2/27)+(2/81)+(2/243)=how much.
(2/3)+(2/9)+(2/27)+(2/81)+(2/243)=多少．
<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">2 / 9</gadget>
<output>2/9 = around 0.222222</output>

<gadget id="calculator">2 / 27</gadget>
<output>2/27 = around 0.074074</output>

<gadget id="calculator">2 / 81</gadget>
<output>2/81 = around 0.024691</output>

<gadget id="calculator">2 / 243</gadget>
<output>2/243 = around 0.00823</output>

<gadget id="calculator">(2/3) + (2/9) + (2/27) + (2/81) + (2/243)</gadget>
<output>242/243 = around 0.995885</output>

<result>242/243 = around 0.995885</result>