<|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 [33, 55, 77, 99], craft an equation that results in 87. You can utilize basic arithmetic operations (+, -, *, /) and each number can only be used once. Present your work in <think> </think> tags. Finally, return your final equation and answer in <answer> </answer> tags. Example format for your answer: <answer> (99 - 77) * (55 / 33) = 87 </answer>.<|im_end|>
<|im_start|>assistant
Let me solve this step by step.
<think>