The minuend is 84, the difference is 40% of the subtrahend, what is the difference.
被减数是84，差是减数的40%，差是多少．
<gadget id="calculator">0.4 - 1</gadget>
<output>-0.6</output>

<gadget id="calculator">1 + 1 + (-0.6)</gadget>
<output>1.4</output>

<gadget id="calculator">84 / 1.4</gadget>
<output>60</output>

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

<gadget id="calculator">60 * (2/5)</gadget>
<output>24</output>

<result>24</result>