Question

An auditorium has 21 rows of seats. The first row has 18 seats, and each succeeding row has two more seats than the previous row. How many seats
are in the auditorium?

Answer 1

An auditorium has 21 rows of seats. The first row has 18 seats

so the next row will have 20 seats in it

so 20 x 20 = 400

now + the extra 18 from first row on

so the total seats = 400 + 18 = 418

Answer 2

isn't there a formula i have to use?

Answer 3

like arithmetic sequences?

Answer 4

@tonipoo610

Answer 5

thats not one of the choices..