
William W. answered 03/20/23
Math and science made easy - learn from a retired engineer
In an arithmetic sequence, you can subtract any two consecutive terms and get the same value (the common difference).
8 - 64 = -56
1 - 8 = -7
Since -56 and -7 are different values, this is NOT an arithmetic sequence.
In a geometric sequence, you can divide any two consecutive terms and get the same value (the common ratio).
8/64 = 0.125 (or 1/8)
1/8 = 0.125 (or 1/8)
Since these are the same values, this IS a geometric sequence and 0.125 (or 1/8) is the common ratio.