Solve for $x$: $\frac{x}{7}+\frac{x}{3}=1-x$.
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Solve for $x$: $\frac{x}{7}+\frac{x}{3}=1-x$.
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
\frac{21}{31}
Solve for $x$: $\frac{x}{7}+\frac{x}{3}=1-x$.
train