<|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 [15, 30, 25, 125], find an equation that equals 100. Utilize basic arithmetic operations (+, -, *, /) and each number can only be used once. Present your work in <think> </think> tags and the final equation and answer in <answer> </answer> tags, for example <answer> 100 = 15 * 30 - 25 * 125 / 15 - 25 * 125 / 15 - 25 * 125 / 15 </answer>.<|im_end|>
<|im_start|>assistant
Let me solve this step by step.
<think>