What is the IQR (Inter Quartile Range) for the data set? 11 6 19 14 21 7 13 15 15


A. 8

B. 9

C. 15

D. 17

1 Answer
May 25, 2017

#IQR=8#

Explanation:

#"arrange the data set in ascending order"#

#6color(white)(x)7color(magenta)(uarr)color(white)(x)11color(white)(x)13color(white)(x)color(red)(14)color(white)(x)15color(white)(x)15color(magenta)(uarr)color(white)(x)19color(white)(x)21#

#"the quartiles 'split' the data set into 4 parts"#

#"the median "color(red)(Q_2)" is the middle value in the data set"#

#rArrcolor(red)(Q_2)=14#

#"the upper quartile "color(magenta)(Q_3)" is between 15 and 19"#

#rArrcolor(magenta)(Q_3)=(15+19)/2=17larr" the average"#

#"the lower quartile "color(magenta)(Q_1)" is between 7 and 11"#

#rArrcolor(magenta)(Q_1)=(7+11)/2=9#

#IQR=color(magenta)(Q_3)-color(magenta)(Q_1)#

#color(white)(IQR)=17-9#

#color(white)(IQR)=8#