What is the difference of all the simplest proper fractions whose fraction unit is (1/6).
分数单位为(1/6)的所有最简真分数的差是多少．
<gadget id="calculator">5 / 6</gadget>
<output>5/6 = around 0.833333</output>

<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">(5/6) - (1/6)</gadget>
<output>2/3 = around 0.666667</output>

<result>2/3 = around 0.666667</result>