As described in z-distribution the answers are given below:
a) The 95% confidence interval estimate for the population mean spending by a customer on visiting salon per month is given as follows: (747, 853).
b) The sampling error at 95% confidence level is of: $35.78.
What is a z-distribution ?
The normal distribution with a mean of 0 and a standard deviation of 1 is referred to as the standard normal distribution (also known as the Z distribution) (the green curves in the plots to the right). It is frequently referred to as the bell curve since the probability density graph resembles a bell.
solution:
The bounds of the confidence interval are given as follows:
In which:
is the sample mean.
z is the critical value.
n is the sample size. is the standard deviation for the population.
The parameters for this problem are given as follows:
Hence the lower bound of the interval is of:
800 - 200 x 1.96/square root of 55 = 747.
The upper bound of the interval is of:
800 + 200 x 1.96/square root of 55 = 853.
The sampling error for a sample size of 120 is calculated as follows:
200 x 1.96/square root of 120 = $35.78.
To learn more about the z-distribution from the given link
brainly.com/question/4079902
#SPJ1
Answer:
yes i think u are correct
Step-by-step explanation:
Answer: Isosceles.
An isosceles triangle is one with two matching side lengths.
Step-by-step explanation:
Answer:
Step-by-step explanation:
A circle with a radius of 5 units has a circumference of 31.416 units.
Answer:
No solution
Step-by-step explanation:
The given equations are :
9x-3y=-6
3x-y=2.....(1)
5y=15x+10
5y-15x=10
or
y-3x=2 .....(2)
Equations (1) and (2) shows that the lines are parallel. We know that for parallel lines, there is no solution.