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Find the sum: 28 is on top of the E, I=1 is on the bottom of the E, and (8i - 13) is on the right side of the E a. 2884 b. 205 c. 3024 d. 211

1 Answer

5 votes
Sum:
∑ (from i = 1 to i = 28) ( 8 i - 13 )
S n = n/2 ( a 1 + a n )
n = 28
a 1 = 8 · 1 - 13 = 8 - 13 = 5
a n = 8 · 28 - 13 = 211
S n = 28/2 · ( - 5 + 211 ) = 14 · 206 = 2,884
Answer: A ) 2,884
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