In 2 years there are 365*2=<<365*2=730>>730 days

So he has learned 730*10=<<730*10=7300>>7300 words

He knew 1/.5=2 times that number of words before the book

So he knew 7300*2=<<7300*2=14600>>14600 words before

# Answer

14600
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Tim buys a book of esoteric words.  He learns 10 words from it a day.  In 2 years the book has increased the number of words he knows by 50%.  How many words did he know originally?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
14600
Tim buys a book of esoteric words.  He learns 10 words from it a day.  In 2 years the book has increased the number of words he knows by 50%.  How many words did he know originally?
train