A piece of cloth is 40% used up for the first time, and 10 meters more than the first time is used for the second time. At this time, there are 30 meters left in this batch of cloth. How many meters is this batch of cloth originally?
一匹布，第一次用去了40%，第二次比第一次多用去10米，此时这批布还剩30米，这批布原来有多少米？
<gadget id="calculator">10 + 30</gadget>
<output>40</output>

<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(2/5) * 2</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">1 - (4/5)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">40 / (1/5)</gadget>
<output>200</output>

<result>200</result>