The subtrahend increases by 5.6, the minuend remains unchanged, how much the difference decreases
减数增加5.6，被减数不变，差减少多少
<gadget id="calculator">10 - 1</gadget>
<output>9</output>

<gadget id="calculator">10 - 6.6</gadget>
<output>3.4</output>

<gadget id="calculator">9 - 3.4</gadget>
<output>5.6</output>

<result>5.6</result>