hello hope all is well with you can you check to see if I did this right please My answer is 11

from the question;
we are given the following numbers
[tex]12,\text{ 1 , 15},\text{ 21, 4, 5, 31, }9,\text{ 8, 11}[/tex]we are to find the range of the numbers
but range is defined as
[tex]\text{Range = Highest value - Lowest value}[/tex]From the numbers
[tex]\begin{gathered} \text{Highest value = 31 } \\ \text{Lowest value = 1} \end{gathered}[/tex]Therefore
[tex]\begin{gathered} \text{Range = 31 - 1} \\ \text{Range = 30} \end{gathered}[/tex]Therefore,
The range of the numbers is 30