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November 3rd, 2016, 01:55 PM   #1
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Arithmetic Sequence & Geometric Sequence Question

I can't formulate a method for the following question:

An arithmetic sequence is defined by un = 12n - 7 and a geometric sequence is defined by vn = 0.3(1.2)^(n-1). Find the least no. of terms such that vn > un.

Could somebody help me out?
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November 3rd, 2016, 03:17 PM   #2
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For n = 41, 12n - 7 = 485
and 0.3(1.2)^(n-1) = 440.9...

For n = 42, 12n - 7 = 497
and 0.3(1.2)^(n-1) = 529.1...

Hence the answer is 42.
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