William W. answered 05/18/20
Experienced Tutor and Retired Engineer
Arithmetic means are the numbers that would be part of an arithmetic sequence where 19 is the 1st term and 52 is the 5th term (in this case) - notice that gives tree numbers in the sequence between the two. Like this:
So:
19 + x + x + x + x = 52
19 + 4x = 52
4x = 52 - 19
4x = 33
x = 33/4 = 8.25
So the 1st arithmetic mean is 19 + 8.25 = 27.25
The 2nd arithmetic mean is 27.25 + 8.25 = 35.5
The 3rd arithmetic mean is 35.5 + 8.25 = 43.75
And then we double check things by adding 43.75 + 8.25 and we do indeed get 52