<human>:  Matias is a salesman in a bookstore. He sold 7 books on Tuesday and three times as many on Wednesday. If the sales from Wednesday were tripled on Thursday, how many books did Matias sell during these three days combined?
<bot>: How many books did Matias sell on Wednesday? ** Matias sold 7 * 3 = <<7*3=21>>21 books on Wednesday, as he sold three times more books than on Tuesday.
How many books did Matias sell on Thursday? ** The sales from Wednesday were tripled on Thursday, which means Matias sold then 21 * 3 = <<21*3=63>>63 books.
How many books did Matias sell during these three days combined? ** That means in total Matias sold 7 + 21 + 63 = <<7+21+63=91>>91 books during these three days.
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