Answer:
The margin of error for the 95% confidence interval for the mean score of all such subjects is of 8.45.
Step-by-step explanation:
We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 27 - 1 = 26
95% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 26 degrees of freedom(y-axis) and a confidence level of 
. So we have T = 2.0518
The margin of error is:
In which s is the standard deviation of the sample and n is the size of the sample.
In this question:
. So
The margin of error for the 95% confidence interval for the mean score of all such subjects is of 8.45.
The full answer would be 83.454 but you can just say 83 pounds. Both are right
Answer:
-7
Step-by-step explanation:
-20 × -7 = 140
140 × -7 = -980
Answer: 34
Step-by-step explanation:
Complete Question
The complete question is shown on the first uploaded image
Answer:
First Question
Option A is correct
Second Question
Option C is correct
Third Question
Fourth Question
So substituting for D in (ABC) D = I
This proof that ABC is invertible
Step-by-step explanation:
From the question we are told that
A , B and C are invertible which means that 
exist
Now
From the question
(ABC) D = I
Where I is an identity matrix
Now when we multiply both sides by 
we have
Now when we multiply both sides by 
we have
Now when we multiply both sides by 
we have
So substituting for D in the above equation
This proof that ABC is invertible
