SOLUTION: A collection of chairs is set up into 22 rows. The first row has 96 chairs, and each row after that one has 2 less chairs than the preceding row. How many total chairs are there

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Question 1084070: A collection of chairs is set up into 22 rows. The first row has
96 chairs, and each row after that one has 2 less chairs than the
preceding row. How many total chairs are there in the collection?

Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
96+94+92+ ...  to 22 terms:

a1 = 96, n = 22, d = -2

S%5Bn%5D=expr%28n%2F2%29%2A%282a%5B1%5D%2B%28n-1%29d%5E%22%22%29

S%5B22%5D=expr%2822%2F2%29%2A%282%2896%29%2B%2822-1%29%28-2%29%5E%22%22%29

S%5B22%5D=11%2A%28192%2B%2821%29%28-2%29%5E%22%22%29

S%5B22%5D=11%2A%28192%2B%28-42%29%5E%22%22%29

S%5B22%5D=11%2A%28192-42%29%5E%22%22%29

S%5B22%5D=11%2A%28150%29%5E%22%22%29

S%5B22%5D=1650%29 chairs

Edwin