He started with 2*4=<<2*4=8>>8 trees

He plants trees for 15-10=<<15-10=5>>5 years

So he planted 5*4=<<5*4=20>>20 trees

So he had 20+8=<<20+8=28>>28 trees

After doubling them he had 28*2=<<28*2=56>>56 trees

# Answer

56
<|im_start|>system
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<|im_start|>user
Jim has 2 rows of 4 trees to start.  When he turns 10 he decides to plant a new row of trees every year on his birthday.  On his 15th birthday after he doubles the number of trees he has.  How many trees does he have?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
56
Jim has 2 rows of 4 trees to start.  When he turns 10 he decides to plant a new row of trees every year on his birthday.  On his 15th birthday after he doubles the number of trees he has.  How many trees does he have?
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