Question

1. In a music stadium, there are 18 seats in the first row and 21 seats in the second row. The number of seats in a row continues to increase by 3 with each additional row. (a) Write an explicit rule to model the sequence formed by the number of seats in each row. Show your work. (b) Use the rule to determine which row has 120 seats. Show your work.

Answer 1

of chairs in each row. 22 -18 = 4. 26 - 18 = 4. So 4 chairs are added to each row

Explanation:

Answer 2

Row 30 will contain 120 seats.

Explanation:

3 chairs will be added each time the row increases. We want to find out which row contains 120 seats. 120 divided by 3 =40, but the first row starts at 18 seats. I grouped 18 to 60 (to make sure I was right) and since 60+60=120 and there was 15 groups, I added 15+15, which equals 30. This is the answer for part B

I believe row 30 has 120 seats.

Hope this helps you :)