Mingming is 1.45 meters tall, while his father is 1.8 meters tall. How many meters taller is he than his father when he stands on a 0.4-meter-high stool?
明明身高1.45米，他爸爸身高1.8米．他站在0.4米高的凳子上时，比他爸爸高多少米？
<gadget id="calculator">0.4 - 1.8</gadget>
<output>-1.4</output>

<gadget id="calculator">1.45 + (-1.4)</gadget>
<output>0.05</output>

<result>0.05</result>