SOLUTION: What is the formula for the nth term of a geometric sequence with a4 = 16 and r = `1/2`? A) `a_(n)=16(1/2)^(n-1)`` B)` `a_(n)=1/2(16)^(n-1)` C)`a_(n)=128(1/2)^(n-1)` D)`a_(

Algebra ->  Sequences-and-series -> SOLUTION: What is the formula for the nth term of a geometric sequence with a4 = 16 and r = `1/2`? A) `a_(n)=16(1/2)^(n-1)`` B)` `a_(n)=1/2(16)^(n-1)` C)`a_(n)=128(1/2)^(n-1)` D)`a_(      Log On


   



Question 936693: What is the formula for the nth term of a geometric sequence with a4 = 16 and r = `1/2`?
A) `a_(n)=16(1/2)^(n-1)``
B)` `a_(n)=1/2(16)^(n-1)`
C)`a_(n)=128(1/2)^(n-1)`
D)`a_(n)=128(2)^(n-1)

Found 2 solutions by stanbon, Fombitz:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
What is the formula for the nth term of a geometric sequence with a4 = 16 and r = `1/2`?
a(4) = a*(1/2)^3 = 16
a = 16/(1/8)
a = 128
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a(n) = 128*(1/2)^(n-1)
Cheers,
Stan H.
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C)`a_(n)=128(1/2)^(n-1)`

Answer by Fombitz(32388) About Me  (Show Source):