1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

10 17 29 39 55 64 28 6 5 3 39 46 35 30 6 32 33 11 20 13 9 14 12 30 56 62 73 54 10 9

1. I need to calculate the upper control limit for the range. It must be a number between 40 and 50 the "Hint" section says. The last tutor gave a value of 84.57 but that was incorrect.
2. How many strata is their in either the mR or the X (same as I) chart? You do not say, as there are many more than 6 strata.