Move the decimal point of 30.5 to the left of the highest digit, what is the difference between the new number and the original number?
把30.5的小数点移到最高位数字的左边，新数与原来的数的差是多少．
<gadget id="calculator">30.5 - 0.305</gadget>
<output>30.195</output>

<result>30.195</result>