Compute
\[\frac{1990^3 - 1000^3 - 990^3}{(1990)(1000)(990)}.\]
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Compute
\[\frac{1990^3 - 1000^3 - 990^3}{(1990)(1000)(990)}.\]
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
3
Compute
\[\frac{1990^3 - 1000^3 - 990^3}{(1990)(1000)(990)}.\]
train