Answer:
The given series converges and 
Step-by-step explanation:
Given is 108, -18, 3,...
It is an alternate series. An alternate series is convergent if:
1. The series is decreasing.
2. If the last term (n-th term) of series converges to 0.
<u>Since each next term is less than its preceding term, so it is decreasing.</u>
First term, a = 108
Second term = -18
Common ratio, r = -18/108 = -1/6
General term, aₙ = a*rⁿ = 108*(-1/6)ⁿ
<u>When n increases to infinity, the exponent term will decreases to zero, and last term (n-th term) will converge to 0 as well.</u>
Hence, the given series converges.
Now limit will be: 

Hence, 
Answer:
Pr(X >42) = Pr( Z > -2.344)
= Pr( Z< 2.344) = 0.9905
Step-by-step explanation:
The scenario presented can be modeled by a binomial model;
The probability of success is, p = 0.65
There are n = 80 independent trials
Let X denote the number of drivers that wear a seat belt, then we are to find the probability that X is greater than 42;
Pr(X > 42)
In this case we can use the normal approximation to the binomial model;
mu = n*p = 80(0.65) = 52
sigma^2 = n*p*(1-p) = 18.2
Pr(X >42) = Pr( Z > -2.344)
= Pr( Z< 2.344) = 0.9905
Answer:
9^2= 81, √25= 5, 21^2= 441, √4= 2, √144= 12, 16^2= 256, √625= 25, (-11)^2=121