Step-by-step explanation:
Geometric Sequence formula for general term:
an = a1(r^n-1)
a1 = 4 × (-5)^1-1
a1 = 4
r = -5
Summation formula for geometric sequence :
Sn = a1 ( 1 - r^n / 1 - r )
...<em>take n from the top of the summation.</em>
= 4 ( 1 -(-5)^6 / 1 -(-5)
= -10416.
Answer: 6
Step-by-step explanation:
Answer:
<h2>A. The series CONVERGES</h2>
Step-by-step explanation:
If
is a series, for the series to converge/diverge according to ratio test, the following conditions must be met.

If
< 1, the series converges absolutely
If
, the series diverges
If
, the test fails.
Given the series 
To test for convergence or divergence using ratio test, we will use the condition above.



aₙ₊₁/aₙ =

note that any constant dividing infinity is equal to zero



Since The limit of the sequence given is less than 1, hence the series converges.
Answer:
1.838181818181818
Step-by-step explanation:
5.4d + 0.1d = 0.66 + 9.45
5.5d = 10.11
d = 10.11 / 5.5
d = 1.838181818181818