Answer:
The explicit form is
Step-by-step explanation:
The explicit form of a geometric sequence is given by:
where an is the nth term, a is the first term of the sequence and r is the common ratio.
In this case:
a=162
The value of the common ratio is obtained by dividing one term by the previous term.
For the first and second terms:
108/162=2/3
For the second and third terms (In order to prove that 2/3 is the common ratio)
72/108=2/3
Therefore:
r=2/3
Replacing a and r in the formula:
Answer:
a) 0.125
b) 7
c) 0.875 hr
d) 1 hr
e) 0.875
Step-by-step explanation:l
Given:
Arrival rate, λ = 7
Service rate, μ = 8
a) probability that no requests for assistance are in the system (system is idle).
Let's first find p.
a) ρ = λ/μ
Probability that the system is idle =
1 - p
= 1 - 0.875
=0.125
probability that no requests for assistance are in the system is 0.125
b) average number of requests that will be waiting for service will be given as:
λ/(μ - λ)
= 7
(c) Average time in minutes before service
= λ/[μ(μ - λ)]
= 0.875 hour
(d) average time at the reference desk in minutes.
Average time in the system js given as: 1/(μ - λ)
= 1 hour
(e) Probability that a new arrival has to wait for service will be:
λ/μ =
= 0.875
Let's analyze the increments for each step of the sequence:
Each step we add 3 to the previous number.
Since we need the 20th, from what we saw, in the 20th term we will have added three 20 times.
So the procedure is: calculate how much is 3 times 20 and then add that to the first term of the sequence.
So we add 60 to the first term to find the 20th term:
Answer: 124
