Answer:
And the 90% confidence interval would be between [566.80 and 579.20]
Step-by-step explanation:
Information given
represent the sample mean
population mean (variable of interest)
s=22 represent the sample standard deviation
n=36 represent the sample size
Confidence interval
The confidence interval for the mean is given by the following formula:
(1)
The degrees of freedom are given by:
The Confidence level is 0.90 or 90%, the significance would be 
and 
, and the critical value for this case would be 
And replacing we got:
And the 90% confidence interval would be between [566.8033 and 579.1967]
Answer:
18
Step-by-step explanation:
The question is asking you to evaluate -4.5b, which is a simplified way of saying
-4.5 * b
Since we know that b = -4, we can insert that instead of b.
-4.5 * -4
The two negatives cancel each other out, so you're left with
4.5 * 4 = 18
Answer:
About 3 years Speedy Jet printers be guaranteed.
Step-by-step explanation:
Given : Quality control studies for Speedy Jet Computer Printers show the lifetime of the printer follows a normal distribution with
mean 
and standard deviation 
If the company wishes to replace no more than 10% of the printers.
To find : How long should Speedy Jet printers be guaranteed ?
Solution :
Using Z- table,
Z value corresponding to 10% or 0.10 = -1.28.
Applying z-score formula,
The value of x is given by,
Substitute the values,
So, approx 3 years.
Therefore, About 3 years Speedy Jet printers be guaranteed.
Answer:
-1.5y
Step-by-step explanation:
+y(–1.5) = -1.5y
This is how distribution works
Answer:
true
Step-by-step explanation:
true
