<|im_start|>system
You are a helpful assistant. You first think about the reasoning process in the mind and then provide the user with the answer. You should try to truely solve the question by yourself without cheating.  <|im_end|>
<|im_start|>user
 The PE teacher places 9 identical soccer balls into three boxes numbered 1, 2, and 3, with the requirement that the number of balls in each box is not less than its number. How many different ways are there to place the balls? Show your work in <think> </think> tags. And return the final answer in <answer> </answer> tags.<|im_end|>
<|im_start|>assistant
Let me solve this step by step.
<think>
user
10
The PE teacher places 9 identical soccer balls into three boxes numbered 1, 2, and 3, with the requirement that the number of balls in each box is not less than its number. How many different ways are there to place the balls?
test