We are asked to count permutations of bottles such that exactly 5 bottles go into their own numbered boxes.
Step 1: Choose 5 positions to be fixed points (i.e., bottle number matches box number).
Number of ways = $\binom{9}{5}$
Step 2: Remaining 4 positions must be a derangement (no bottle goes into its matching box).
Let $D_4$ be the number of derangements of 4 items.
$D_4 = 9$
Step 3: Total ways = $\binom{9}{5} \times D_4 = 126 \times 9 = 1134$
✅ Final Answer: $\boxed{1134}$
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