remolatg
2020-11-06
Answered

Find the median and quartiles for the data.

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SoosteethicU

Answered 2020-11-07
Author has **102** answers

Calculation:

Median:

- If the data set consists of odd number of entries then the median is the middle value of the data.

- If the data set consists of even number of entries then the median is the mean of the middle vales in the data set.

Arrange the data in ascending order.

120, 120, 130, 140, 150, 150, 150, 160, 180

Here the number of observations is 9 which is an odd number. Therefore the median is the center value of the data that is, 150

Thus, the median cost of compact refrigerators is$\mathrm{\$}150$ .

First quartile${Q}_{1}$ :

The median of the data values that are to the left of the overall median is termed as first quartile.

Here the number of observation below median is 4 which is an even number.

The middle values represent${2}^{nd}$ observation and ${3}^{rd}$ observation.

Here the${2}^{nd}$ observation is 120 and ${3}^{rd}$ observation is 130.

${Q}_{1}=\frac{120+130}{2}$

$=\frac{250}{2}=125$

Thus, the first quartile${Q}_{1},\text{}is\text{}\mathrm{\$}125$ .

Third quartile${Q}_{3}$ :

The median of the data entries that are to the right of the overall median is termed as third quartile

Here the number of observation above median is 4 which is an even number.

The middle values represent${7}^{th}\text{}and\text{}{8}^{th}$ observations.

Here the${7}^{th}$ observation is 150 and ${8}^{th}$ observation is 160.

${Q}_{3}=\frac{150+160}{2}$

$=\frac{310}{2}=155$

Thus, the third quartile${Q}_{3},\text{}is\text{}\mathrm{\$}155$ .

Median:

- If the data set consists of odd number of entries then the median is the middle value of the data.

- If the data set consists of even number of entries then the median is the mean of the middle vales in the data set.

Arrange the data in ascending order.

120, 120, 130, 140, 150, 150, 150, 160, 180

Here the number of observations is 9 which is an odd number. Therefore the median is the center value of the data that is, 150

Thus, the median cost of compact refrigerators is

First quartile

The median of the data values that are to the left of the overall median is termed as first quartile.

Here the number of observation below median is 4 which is an even number.

The middle values represent

Here the

Thus, the first quartile

Third quartile

The median of the data entries that are to the right of the overall median is termed as third quartile

Here the number of observation above median is 4 which is an even number.

The middle values represent

Here the

Thus, the third quartile

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My notes on confidence give this question:

An investigator is interested in the amount of time internet users spend watching TV a week. He assumes

Since

The investigator collects that data and obtain

With the answer that:

No he cannot, because the probability describes the method/estimator, not the result. We say that "we conclude with 99% confidence that the error does not exceed 1.27 hours."

I am confused. What is this difference between probability and confidence? Is it related to confidence intervals? Is there an intuitive explanation for the difference?

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