Using the data you gave I made an equation
(x+3+11+9+7+3)/6 = x
(The formula for finding the mean is the sum of observations divided by total no of observations)
And I equated it (refer the picture)
x = 33/5 = 6.6
Hope this helped you!
(x+3+11+9+7+3)/6 = x
(The formula for finding the mean is the sum of observations divided by total no of observations)
And I equated it (refer the picture)
x = 33/5 = 6.6
Hope this helped you!