<PRE><B>Question 944648</B>
please help solve these two problems:
 sequence 4,8,16,32,64,128…
 Note:: This is a Geometric Sequence
 r = 8/4 = 2
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a(1) = 4
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 prob #1: a(3) what is a?
a(3) = a*r^2 = 4*2^2 = 16
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 prob #2: a(1)+a(7) = 4 + 4*r^6 = 4 + 4*2^6 = 4+4*64 = 4+256 = 260
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Cheers,
Stan H.
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