There are 1260 seats in a row, each other row decreases by 12 each time, how many rows are there and how many seats are there?

Question

There are 1260 seats in a row, each other row decreases by 12 each time, ho

Answer 1

1260 divided by 12 equals 105, so the number of rows is 105 and the totality of seats is

12 + 24 + ... + 12+(104)(12).

 

This is an arithmetic series, and you can use the formula for that sum, based on the pattern I have shown above.