[tex]\huge\mathcal\purple{SolutioN :}[/tex]
On arranging the given data in ascending order of their magnitudes, we get :
➙ 7 , 9 , 11 , 13 , 15 , 17 , 19
Clearly, n = 7, which is an odd number.
★ Lower Quartile (Q¹)
[tex] = > ( \frac{n + 1}{4} )term \: [/tex]
[tex] = > ( \frac{7 + 1}{4} ) \: term[/tex]
[tex] = > 2nd \: \: term \: = > 9[/tex]
★ Upper Quartile (Q³)
[tex] = > ( \frac{3(7 + 1)}{4} ) \: term[/tex]
[tex] = > 6th \: term \: = > 17[/tex]
★ Inter-Quartile range
⇒ Q³- Q¹
⇒ 17 - 9
⇒ 8
[tex]\huge\purple{✎﹏﹏﹏﹏﹏﹏﹏﹏﹏}[/tex]