When Xiao Ming divided 30.6 by a number, because the decimal point of the quotient was one more to the right, the result was 20.4. What is the divisor of this question?
小明在计算30.6除以一个数时，由于商的小数点向右多点了一位，结果得20.4，这道题的除数是多少？
<gadget id="calculator">30.6 / 20.4</gadget>
<output>1.5</output>

<result>1.5</result>