Answer:
M = (-3,1)
Step-by-step explanation:
We need to find the midpoint M of the line segment joining the points
A = (-5,7) and B = (-1, -5)
The mid point of the line segment joining the points (x₁,y₁) and (x₂,y₂) is given by :

Hence, the required point is (-3,1).
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Answer with explanation:</u></h2>
The confidence interval for population mean (when population standard deviation is unknown) is given by :-

, where n= sample size
= Sample mean
s= sample size
t* = Critical value.
Given : n= 25
Degree of freedom : 

Significance level for 98% confidence interval : 
Using t-distribution table ,
Two-tailed critical value for 98% confidence interval :

⇒ The critical value that should be used in constructing the confidence interval = 2.4922
Then, the 95% confidence interval would be :-




Hence, the 98% confidence interval for the mean repair cost for the dryers. = 
Answer:64
Step-by-step explanation:
67
Answer: The value of test statistic is 2.442.
Step-by-step explanation:
Since we have given that
n = 238
Sample mean = 23.2 minutes
Standard deviation = 20.26 minutes
Hypothesis :

So, the test statistic value would be

Hence, the value of test statistic is 2.442.