[tex]\begin{gathered} \text{First step }organize\text{ the data} \\ 1,\text{ }2,\text{ 4, 4, 6, 7, 9, 12} \\ Second\text{ step calculate median} \\ \operatorname{median}\text{ =}\frac{4+6}{2}=\frac{10}{2}\text{ = 5} \\ Median\text{ is 5} \\ \text{Thrid step} \\ -\text{ For the first four numbers, calculate the median} \\ 1,\text{ }2,\text{ 4, 4} \\ \operatorname{median}\text{ 1=}\frac{2+4}{2}=\frac{6}{2}=3 \\ \\ -\text{ For the second four numbers, calculate the median} \\ \text{6, 7, 9, 12} \\ \operatorname{median}\text{ 2=}\frac{7+9}{2}=\frac{16}{2}=8 \\ \operatorname{median}\text{ 2=}8 \\ \\ \text{Interquartile range =median 2-median 1} \\ \text{Interquartile range =8-3} \\ \text{Interquartile range =}5 \\ \text{the Interquartile range is 5} \end{gathered}[/tex]
