<|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
Use the numbers [15, -15, 107, 57], combining them with some of the following operations: +, -, *, /, to make 415. Your work must show the final solution in <think> tags. Please return the final equation you used to solve the problem in <answer> tags, for example <answer> (-15 + 107) * 15 - 57 = 415 </answer>.<|im_end|>
<|im_start|>assistant
Let me solve this step by step.
<think>