Quartiles tell us about the spread of a data set by breaking the data set into quarters, just like the median breaks it in half. For example, consider the marks of the 100 students below, which have been ordered from the lowest to the highest scores, and the quartiles highlighted in red.

Example: 5, 7, 4, 4, 6, 2, 8 And the result is: Quartile 1 (Q1) = 4. Quartile 2 (Q2), which is also the Median, = 5.

Subsequently, What does the first quartile tell us about data?

The fact that 72.5 is the 1st quartile tells us that a quarter of the data values are less than 25, and the rest of them are higher than 25. … and the 3rd quartile will be the median of this half of the list. So the 3rd quartile is 75.5.

Also, How do you calculate Q1 and Q3?

Q1 is the median (the middle) of the lower half of the data, and Q3 is the median (the middle) of the upper half of the data. (3, 5, 7, 8, 9), | (11, 15, 16, 20, 21). Q1 = 7 and Q3 = 16.

What does the first quartile represent?

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.

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## How are quartiles calculated?

The quartile measures the spread of values above and below the mean by dividing the distribution into four groups. A quartile divides data into three pointsâ€”a lower quartile, median, and upper quartileâ€”to form four groups of the dataset.

## How do you find Q1 Q2 Q3 in statistics?

Q1 is the “middle” value in the first half of the rank-ordered data set. Q2 is the median value in the set. Q3 is the “middle” value in the second half of the rank-ordered data set.

## What is the Q1 of a data set?

Q1 is the middle value in the first half of the data set. Since there are an even number of data points in the first half of the data set, the middle value is the average of the two middle values; that is, Q1 = (3 + 4)/2 or Q1 = 3.5. Q3 is the middle value in the second half of the data set.

## What does Q1 and Q3 represent?

The values that divide each part are called the first, second, and third quartiles; and they are denoted by Q1, Q2, and Q3, respectively. Q1 is the “middle” value in the first half of the rank-ordered data set. Q2 is the median value in the set. Q3 is the “middle” value in the second half of the rank-ordered data set.

## How do you find Q1 and Q2 in statistics?

Q1 is the “middle” value in the first half of the rank-ordered data set. Q2 is the median value in the set. Q3 is the “middle” value in the second half of the rank-ordered data set.

## What does the 3rd quartile represent?

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 .

## What is third quartile example?

An Example In other words, the median is: (7 + 8)/2 = 7.5. Here the median is (15 + 15)/2 = 15. Thus the third quartile Q3 = 15.

## How are quartiles used in real life?

Some companies use the quartiles to benchmark other companies. For example, the median company pay for a given position is set at the first quartile of the top 20 companies in that region. The quartiles and IQR information is typically used when you create a box-plot of your data set.

## How do you find Q2 in statistics?

– Quartile 1 (Q1) = (4+4)/2 = 4.
– Quartile 2 (Q2) = (10+11)/2 = 10.5.
– Quartile 3 (Q3) = (14+16)/2 = 15.

## How do you find the quartiles of a data set?

– Quartile 1 (Q1) = (4+4)/2 = 4.
– Quartile 2 (Q2) = (10+11)/2 = 10.5.
– Quartile 3 (Q3) = (14+16)/2 = 15.

## What does the first quartile tell you?

The fact that 72.5 is the 1st quartile tells us that a quarter of the data values are less than 25, and the rest of them are higher than 25. … and the 3rd quartile will be the median of this half of the list. So the 3rd quartile is 75.5.

## What is a 3rd quartile?

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 .

## How do you find the Q1 of a data set?

Q1 is the middle value in the first half of the data set. Since there are an even number of data points in the first half of the data set, the middle value is the average of the two middle values; that is, Q1 = (3 + 4)/2 or Q1 = 3.5.

## How much data is between Q1 and Q3?

3. Providing insight into interesting properties of the data. 34Since Q1 and Q3 capture the middle 50% of the data and the median splits the data in the middle, 25% of the data fall between Q1 and the median, and another 25% falls between the median and Q3.

## How do you find quartiles in statistics?

Find Quartiles: Examples Step 1: Put the numbers in order: 2, 5, 6, 7, 10, 12 13, 14, 16, 22, 45, 65. Step 2: Count how many numbers there are in your set and then divide by 4 to cut the list of numbers into quarters. There are 12 numbers in this set, so you would have 3 numbers in each quartile.