please read the photo above first :))
a) 40
b) 160
c) 240
d) 320
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Answer: A
Step-by-step explanation:
This problem, may seem abit tricky, but this sequence is all about plugging in.
Since c₁=5, we can solve for c₂ and c₃.
c₂=c₁·2ⁿ⁻¹
c₂=5·2¹
c₂=10
Now that we have c₂, we can find c₃.
c₃=c₂·2ⁿ⁻¹
c₃=10·2²
c₃=40