The school prepared 40 x 20 = <<40*20=800>>800 chairs.

So, 800 - 10 = <<800-10=790>>790 chairs were taken.

# Answer

790
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
For the school play, 40 rows of chairs were set up where there were 20 chairs in each row. If only 10 seats were not occupied, how many seats were taken?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
790
For the school play, 40 rows of chairs were set up where there were 20 chairs in each row. If only 10 seats were not occupied, how many seats were taken?
train