I've attached the complete question.
Answer:
Only participant 1 is not cheating while the rest are cheating.
Because only participant 1 has a z-score that falls within the 95% confidence interval.
Step-by-step explanation:
We are given;
Mean; μ = 3.3
Standard deviation; s = 1
Participant 1: X = 4
Participant 2: X = 6
Participant 3: X = 7
Participant 4: X = 0
Z - score for participant 1:
z = (x - μ)/s
z = (4 - 3.3)/1
z = 0.7
Z-score for participant 2;
z = (6 - 3.3)/1
z = 2.7
Z-score for participant 3;
z = (7 - 3.3)/1
z = 3.7
Z-score for participant 4;
z = (0 - 3.3)/1
z = -3.3
Now from tables, the z-score value for confidence interval of 95% is between -1.96 and 1.96
Now, from all the participants z-score only participant 1 has a z-score that falls within the 95% confidence interval.
Thus, only participant 1 is not cheating while the rest are cheating.
The value for x is 9 because:
7x +49 = 2x + 94
7x-2x=45
5x=45
x=45/5
x=9
Answer:
a) x = 1.52
b) s = 1.16
Step-by-step explanation:
We have that:
5 students watched 0 movies.
9 students watched 1 movie.
5 students watched 2 movies.
5 students watched 3 movies.
1 student watched 4 movies.
(a) Find the sample mean x.
Sum divided by the number of students. So

(b) Find the approximate sample standard deviation, s.
Standard deviation of the sample.
Square root of the sum of the squares of the values subtracted from the mean, divided by the sample size subtracted by 1. So
