Plz help it’s due tomorrow

In an examination of purchasing patterns of shoppers, a sample of 16 shoppers revealed that they spent, on average, $54 per hour

Lesechka [4]

Answer:

$54-1.64\frac{21}{\sqrt{16}}=45.39$

$54 +1.64\frac{21}{\sqrt{16}}=62.61$

So on this case the 90% confidence interval would be given by (45.39;62.61)

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

$\bar X=54$ represent the sample mean

$\mu$ population mean (variable of interest)

$\sigma=21$ represent the sample standard deviation

n=16 represent the sample size

Solution to the problem

The confidence interval for the mean is given by the following formula:

$\bar X \pm z_{\alpha/2}\frac{\sigma}{\sqrt{n}}$ (1)

Since the Confidence is 0.90 or 90%, the value of $\alpha=1-0.9=0.1$ and $\alpha/2 =0.05$ , and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-NORM.INV(0.05,0,1)".And we see that $z_{\alpha/2}=1.64$

Now we have everything in order to replace into formula (1):

$54-1.64\frac{21}{\sqrt{16}}=45.39$

$54 +1.64\frac{21}{\sqrt{16}}=62.61$

So on this case the 90% confidence interval would be given by (45.39;62.61)

4 0

4 years ago

The temperature at midnight was 3°. By 6am, the temperature had dropped 5°. What was the temperature at 6am?

Annette [7]

The temperature at 6am would've been -2 because 3 - 5 = -2

8 0

3 years ago

The histogram below represents the high temperatures recorded each day over month period. Which of the following statements are

Kisachek [45]

Answer:

See possible solutions below.

Step-by-step explanation:

The statements are not given. But the following can be determined from the graph:

More days recorded temperatures between 82 and 84 then other temperatures.
The least number of days recorded temperatures between 88 and 90.
The histogram is skewed to the right also known as positive skewed distribution.
The mean and median will most likely be in the range of 82-84 temperatures. But the mean will be greater than the median.

4 0

3 years ago

I’ll give Brainly! What is the solution to x - 5 = 27? A) 135 B) 22 C) 27 D) 32

Eddi Din [679]

Answer: D) 32

Step-by-step explanation:

1. You have to add 5 on both side which you get x=32

2. x=32 which means 32 is the # for x

:)

5 0

3 years ago

Graph the inverse of the function.