The product of 4.8 and 7.2 is exactly 100 after adding a number. What is this number?
4.8与7.2的积，加上一个数后正好得100，这个数是多少？
<gadget id="calculator">4.8 * 7.2</gadget>
<output>34.56</output>

<gadget id="calculator">100 - 34.56</gadget>
<output>65.44</output>

<result>65.44</result>