Find the​ range, variance, and standard deviation for the given sample data120 142 143 130 129 122

Question

I solve the range which is 23

Answer 1

There are two ways to solve the range. You can do high-low (143-120)which will get you the 23. Or you can do another way which is high-low+1 (143-120+1), which will give you 24. The +1 is sometimes added to give the full spread of the data from the lowest number to the highest number. 

 

The variance is 94.4 and the standard deviation is 9.71.