There is a rope. If you cut it 6 meters to the right of the midpoint, the ratio of the lengths of the two ropes is 3:1. What is the original length of the rope?
有一条绳子，如果在距离中点右边6米处剪一下，得到两段绳子的长度之比是3：1，这条绳子原来长多少米．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 + 3</gadget>
<output>4</output>

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

<gadget id="calculator">(1/2) - (1/4)</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">6 / (1/4)</gadget>
<output>24</output>

<result>24</result>