<PRE><B>Question 1189156</B>


21,24,19,32,15,43,38,39 

 
To find the lower quartile of a set of data, we can find the median of the data and then find the median of the first half.


15,19,21,24,......32,38,39,43

median={{{(24+32)/2=28}}}

15,19....,21,24

Q1={{{(19+21)/2=20}}}

32,38....,39,43

Q3={{{(38+39)/2=38.5}}}

Interquartile Range: IQR = Q3 - Q1={{{38.5-20=18.5}}}

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