If $131_{a}$ is equal to the base 10 integer 55, find $a$ given that $a>0$.
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
If $131_{a}$ is equal to the base 10 integer 55, find $a$ given that $a>0$.
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
6
If $131_{a}$ is equal to the base 10 integer 55, find $a$ given that $a>0$.
train