Firstly, Subtract the smallest number from the largest number
26 - - 2 = 28
28 spans over 5 numbers so we divide it to figure out the difference between each number
28 / 5 = 5.6
-2 is the 1st number
+5.6
3.6 is the 2nd number
+5.6
9.2 is the 3rd number