The quotient of 12.5/0.4 is 31, what is the remainder?
12.5/0.4的商是31，余数是多少．
<gadget id="calculator">0.4 * 31</gadget>
<output>12.4</output>

<gadget id="calculator">12.5 - 12.4</gadget>
<output>0.1</output>

<result>0.1</result>