Question

Determine whether the sequence converges or diverges. If it converges, give the limit.

Answer 1

Answer:

  Converges; 51 3/7

Step-by-step explanation:

The common ratio is -10/60 = (5/3)/-10 = (-5/18)/(5/3) = -1/6.

Then the sum of the sequence is given by ...

  S = a1/(1 -r) = 60/(1 -(-1/6))

  S = 60/(7/6) = 360/7

  S = 51 3/7

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If you erroneously evaluate the formula for the sum using +1/6 as the common ratio, then you will get S=60/(1-1/6) = 60·6/5 = 72.