Question

7. a hockey arena has 10 920 seats. the first row of seats around the rink has 220 seats. the number of seats in each subsequent row increases by 16. how many rows of seats does the arena have?

Answer 1

The number of rows in the arena is 26

How to determine the number of rows?

The hockey arena illustrates an arithmetic sequence, and it has the following parameters:

• First term, a = 220
• Sum of terms, Sn = 10920
• Common difference, d = 16

The number of rows (i.e. the number of terms) is calculated using:

$S_n = \frac{n}{2}(2a + (n -1) * d)$

So,we have:

$10920 = \frac{n}{2}(2 * 220 + (n -1) * 16)$

Evaluate the terms and factors

$21840 = n(440 + 16n -16)$

Evaluate the like terms

21840 = n(424+ 16n)

Expand

21840 = 424n + 16n^2

Rewrite as:

16n^2 + 424n - 21840 = 0

Using a graphical tool, we have:

n = 26

Hence, the number of rows in the arena is 26

Read more about arithmetic sequence at:

brainly.com/question/6561461

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