Question

What is the third quartile, Q3, of the following distribution?

4, 5, 33, 10, 12, 14, 34, 43, 21, 22, 21, 22, 44, 29, 16, 18, 20, 24, 26, 29
A. 10
B. 29
C. 24
D. 22
E. 4

Answer 1

The lower half of a data set is the set of all values that are to the left of the median value when the data has been put into increasing order.
The upper half of a data set is the set of all values that are to the right of the median value when the data has been put into increasing order.
The first quartile, denoted by Q1 , is the median of the lower half of the data set. This means that about 25% of the numbers in the data set lie below Q1 and about 75% lie above Q1 .
The third quartile, denoted by Q3 , is the median of the upper half of the data set. This means that about 75% of the numbers in the data set lie below Q3 and about 25% lie above Q3

Answer 2

so i find the median then sperate it then do the median again?

Answer 3

sort of

Answer 4

Find the first and third quartiles of the data set {3, 7, 8, 5, 12, 14, 21, 13, 18}.

First, we write data in increasing order: 3, 5, 7, 8, 12, 13, 14, 18, 21.

Quartile1.PNG

As on the previous page, the median is 12.

Therefore, the lower half of the data is: {3, 5, 7, 8}.

The first quartile, Q1, is the median of {3, 5, 7, 8}.

Since there is an even number of values, we need the mean of the middle two values to find the first quartile:

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Similarly, the upper half of the data is: {13, 14, 18, 21}, so

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Example 2: Find the first and third quartiles of the set {3, 7, 8, 5, 12, 14, 21, 15, 18, 14}.

Note that here we consider the two 14's to be distinct elements and not representing the same item; consider this like you obtained a score of 14 on two different quizzes.

First, we write the data in increasing order: 3, 5, 7, 8, 12, 14, 14, 15, 18, 21.

As before, the median is 13 (it is the mean of 12 and 14 — the pair of middle entries).

Therefore, the lower half of the data is: {3, 5, 7, 8, 12}.

Notice that 12 is included in the lower half since it is below the median value.

Then Q1 = 7 (there are five values in the lower half, so the middle value is the median). Similarly, the upper half of the data is: {14, 14, 15, 18, 21}, so Q3 = 15.



this is an example i found

Answer 5

so median of it all then sperate in thirds then mediam again

Answer 6

you basically find the middle of every set you get

Answer 7

yea that makes sence

Answer 8

such as if you have 1,2,3,4,5,6,7,8,9,10,11,12

Answer 9

okay i understand

Answer 10

median would be 6

Answer 11

then find the median of 7 8 9 10 11 and 12

Answer 12

that would be q 3

Answer 13

cool