Question

In an auditorium, there are 21 seats in the first row and 29 seats in the second row. The number of seats in a row continues to increase by 8 with each additional row.
(a) How many seats are in the 3rd,4th, and 5th rows.
(b) Is this an arithmetic or geometric sequence?
(c) How would you find the 100th row?

Answer 1

Step-by-step explanation:

a) The 3rd row has 37 seats, the 4th row has 45 seats and the 5th row has 53 seats.

b) This is an arithmetic sequence because the values differ by a constant quantity.

c) You need to find the nth term of the sequence:

    21 = 1×8+x

    x=13

So the nth term is 8x +13.

The 100th term would be 813.