After subtracting (2/5) from a number, the remaining number is divided by 4, and the result is (3/4). Find this number.
一个数减去它的(2/5)后，剩下的数除以4，结果是(3/4)．求这个数．
<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

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

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

<gadget id="calculator">(2/5) * (1/4)</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">(1/4) - (1/10)</gadget>
<output>3/20 = around 0.15</output>

<gadget id="calculator">(3/4) / (3/20)</gadget>
<output>5</output>

<result>5</result>