Cut off (2/3) of a piece of cloth, and there are 30 meters left. How many meters is this piece of cloth?
一段布剪去它的(2/3)，还剩30米，这段布原有多少米？
<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">1 - (2/3)</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">30 / (1/3)</gadget>
<output>90</output>

<result>90</result>