Answer:
1094
Explanation:
The sum of terms of a geometric series is given by ...
Sn = a1·(r^n -1)/(r -1)
You want the sum for ...
a1 = 2, r = -3, n = 7
Filling in the numbers, we get ...
S7 = 2·((-3)^7 -1)/(-3-1) = 2(-2188)/(-4)
S7 = 1094
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