Identify the 16th term of a geometric sequence where a1 = 4 and a8 = - 8,748.

-172,186,884

-57,395,628

57,395,628

172,186,884

-57,395,628

Step-by-step explanation:

The n-th term of a geometric sequence is given by ...

an = a1·r^ (n-1)

Then the ratio of the 8th term to the 1st term is ...

a8/a1 = (a1·r^ (8-1)) / (a1·r^ (1-1)) = r^7

and the common ratio is ...

(-8748/4) ^ (1/7) = - 3

That makes the 16th term be ...

a16 = 4· (-3) ^ (16 - 1) = - 57,395,628