write a general term to find the number of flowers in the nth row when the first row has 42 flowers, 2nd has 40 flowers the 3rd has 38 flowers..etc..i need a general term to determine the total number of flowers you need to plant n rows of flowers?
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What your looking for is the arithmetic series
Formula for arithmetic series is
S(n) = (n/2) * (42 + (-2n + 44))
Now to test:
S(3) = (3/2) * (42 + (-2(3) + 44))
= 1.5 * (42 + 38)
= 1.5 * (80) = 120
Formula for arithmetic series is
S(n) = (n/2) * (42 + (-2n + 44))
Now to test:
S(3) = (3/2) * (42 + (-2(3) + 44))
= 1.5 * (42 + 38)
= 1.5 * (80) = 120