rope is (8/21) meters long. Cut off half of it first, and then cut the rest in half... After cutting 4 times, how many meters is the length of the remaining part?
一根绳子长(8/21)米，先剪下它的一半，再把剩下的剪下一半…剪4次后，剩下的部分长多少米．
<gadget id="calculator">8 / 21</gadget>
<output>8/21 = around 0.380952</output>

<gadget id="calculator">(8/21) / 2 / 2 / 2 / 2</gadget>
<output>1/42 = around 0.02381</output>

<result>1/42 = around 0.02381</result>