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?
How many chairs were set up? ** The school prepared 40 x 20 = <<40*20=800>>800 chairs.
How many chairs were taken? ** So, 800 - 10 = <<800-10=790>>790 chairs were taken.
#### 790