Question

PLEASE HELP I WILL MARK YOU AS BRAINLEST

Answer 1

Answer:

2.5

Step-by-step explanation:

16, 17, 18, 18, 18, 18, 19, 19, 20, 21, 23, 26

Median: 18.5

Lower quartile: 18

Upper quartile: 20.5

Interquartile range: 20.5 - 18 = 2.5

Answer 2

Answer:

(i) Five number summary: Minimum value = 1, $Q_1=18$,$Median=18.5$, $Q_3=20.5$, Maximum value = 26.

(ii) IQR = 2.5, upper fence = 24.25 and lower fence = 14.25.

(iii) 26 is an outlier of the data.

Step-by-step explanation:

The given data set is

19, 18, 23, 18, 18, 26, 19, 16, 20, 18, 17, 21

Arrange the data set in ascending order.

16, 17, 18, 18, 18, 18, 19, 19, 20, 21, 23, 26

Divide the data set in 4 equal parts.

(16, 17, 18), (18, 18, 18), (19, 19, 20), (21, 23, 26)

Minimum value = 16

$Q_1=\frac{18+18}{2}=18$

$Median=Q_2=\frac{18+19}{2}=18.5$

$Q_3=\frac{20+21}{2}=20.5$

Maximum value = 26

The inter quartile range (IQR) of the data is

$IQR=Q_3-Q_1=20.5-18=2.5$

Upper fence :

$Q_3+1.5(IQR)=20.5+1.5(2.5)=24.25$

Lower fence :

$Q_1-1.5(IQR)=18-1.5(2.5)=14.25$

If the any element of the data set lies out side the upper fence and lower fence, then it is called an outlier.

26 ∉ [14.25, 24.25]

Therefore, 26 is an outlier of the data.