Answer:
We need a sample size of at least 75.
Step-by-step explanation:
We have that to find our 
level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Ztable as such z has a pvalue of 
.
So it is z with a pvalue of 
, so 
Now, we find the margin of error M as such
In which 
is the standard deviation of the population and n is the size of the sample.
The standard deviation is the square root of the variance. So:
With a .95 probability, the sample size that needs to be taken if the desired margin of error is 5 or less is
We need a sample size of at least n, in which n is found when M = 5. So
We need a sample size of at least 75.
Answer:
227.5
Step-by-step explanation: You have to multiply 3.5 times 65
Hope this helps!!!
Answer:
a. (4, 13/6)
b. (4, -5/6)
c. (4, 5/6)
Step-by-step explanation:
sorry if it is not right.
Answer:
P(X > 5) = 0.1164 to 4 d.p.
The parameters are defined in the explanation.
Step-by-step explanation:
This is a binomial distribution problem
Binomial distribution function is represented by
P(X = x) = ⁿCₓ pˣ qⁿ⁻ˣ
n = total number of sample spaces = number of potential hires = 10
x = Number of successes required = number of potential hires that have prior call centre experience = more than half; that is, x > 5
p = probability of success = probability that any potential hire will have experience = (11/30) = 0.367
q = probability of failure = probability that any potential hire will NOT have experience = 1 - p = 1 - 0.367 = 0.633
P(X > 5) = P(X=6) + P(X=7) + P(X=8) + P(X=9) + P(X=10)
Inserting the parameters and computing the probabilities for each of those values of X,
P(X > 5) = 0.11641775484 = 0.1164 to 4 d.p.
Hope this Helps!!!
-2a + 3b = 9 / x 2;
-4a + 6b = 18;
Then, -4a + 6b = 18
+4a - 2b = 3
__________________(+)
We obtain 4b = 21;
b = 21/4;
-2a + 63/4 = 9;
-8a + 63 = 36;
-8a = - 27;
a = 27/8 ;
