Add 0.2 to the minuend and subtract 0.02 from the subtrahend, how much will the difference increase.
被减数加上0.2，减数减去0.02，差将增加多少．
<gadget id="calculator">10 + 0.2</gadget>
<output>10.2</output>

<gadget id="calculator">4 - 0.02</gadget>
<output>3.98</output>

<gadget id="calculator">10.2 - 3.98</gadget>
<output>6.22</output>

<gadget id="calculator">10 - 4</gadget>
<output>6</output>

<gadget id="calculator">6.22 - 6</gadget>
<output>0.22</output>

<result>0.22</result>