There are two piles of coal, take out (1/5) from pile A, and take out (1/4) from pile B. At this time, the remaining amount of coal in the two piles is the same. The original coal of Pile A is 75 tons, how many tons of original coal of Pile B?
有两堆煤，从甲堆中取出(1/5)，从乙堆中取出(1/4)，这时两堆煤剩下的数量同样多．甲堆原有煤75吨，乙堆原有煤多少吨？
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

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

<gadget id="calculator">1 - (1/4)</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">(4/5) / (3/4)</gadget>
<output>16/15 = around 1.066667</output>

<gadget id="calculator">75 * (16/15)</gadget>
<output>80</output>

<result>80</result>