<|im_start|>system
You are a helpful assistant. You first thinks about the reasoning process in the mind and then provides the user with the answer.<|im_end|>
<|im_start|>user
Using the numbers [1, 11, 13, 55], create an equation that equals 9 using basic arithmetic operations (+, -, *, /) without repeating any number. Show your work in <think> </think> tags. Return the final equation and solution in <answer> </answer> tags, for example <answer> (2 + 1) - 1 = 2 </answer>.<|im_end|>
<|im_start|>assistant
Let me solve this step by step.
<think>