If the minuend increases by 2.7 and the subtrahend decreases by 1.5, how much will their difference increase?
如果被减数增加2.7，减数减少1.5，它们的差将增加多少．
<gadget id="calculator">2.5 - 1.5</gadget>
<output>1</output>

<gadget id="calculator">2.7 - 1 - 1</gadget>
<output>0.7</output>

<gadget id="calculator">3.5 + 0.7</gadget>
<output>4.2</output>

<result>4.2</result>