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
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Answer:
50+0.03x
Step-by-step explanation:
All you need to do is look at the numbers given in the word problem and convert them to algebraic terms.
Answer:
x=3
Step-by-step explanation:
14=7(2x-4)
14/7=2x-4
2=2x-4
2x=2+4
2x=6
x=6/2
x=3
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14=7(2x-4)
14=14x-28
14x=14+28
14x=42
x=42/14
x=3
