There is a batch of books distributed to 6 children on average, and the result is 3 more books. The average distribution to 8 children is also 5 more. There are 6 more books distributed to 9 children on average. How many books are there at least in this batch?
有一批书平均分给6个小朋友，结果多3本．平均分给8个小朋友也多5本．平均分给9个小朋友还多6本，这批书最少有多少本？
<gadget id="calculator">2 * 3 * 2 * 2 * 3</gadget>
<output>72</output>

<gadget id="calculator">72 - 3</gadget>
<output>69</output>

<result>69</result>