On Tuesday, 120 books were taken out 250 - 120 = <<250-120=130>>130 books

On Wednesday, 35 books were returned 130 + 35 = <<130+35=165>>165 books

On Thursday, 15 books were borrowed 165 - 15 = 150 books

# Answer

150
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
There are 250 books inside a library. On Tuesday, 120 books are taken out to be read by children. On Wednesday, 35 books are returned. On Thursday, another 15 books are withdrawn from the library. How many books are now in the library?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
150
There are 250 books inside a library. On Tuesday, 120 books are taken out to be read by children. On Wednesday, 35 books are returned. On Thursday, another 15 books are withdrawn from the library. How many books are now in the library?
train