The sum of the minuend, the subtrahend and the difference is 10.8. It is known that the subtrahend is 80% of the difference. What is the subtrahend?
被减数、减数与差的和是10.8，已知减数是差的80%，减数是多少．
<gadget id="calculator">10.8 / 3.6</gadget>
<output>3</output>

<gadget id="calculator">80 / 100</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">3 * (4/5)</gadget>
<output>12/5 = around 2.4</output>

<result>12/5 = around 2.4</result>