Isaac keeps track of the miles per gallon his car gets per week. he has accumulated the following data:
(1, 24), (2, 24.48), (3, 24.97), (4, 25.47)
what is the common difference or ratio?

1) Try the difference between consecutive terms:

24.48 - 24 = 0.48

24.97 - 24.48 = 0.49

25.47 - 24.97 = 0.50

As you see the difference is not constant (common)

2) Try the ratio between consecutive terms;

24.48 / 24 = 1.0200

24.97 / 24.48 = 1.0200

25.47 / 24.97 = 1.0200

So, you conclude that the common ratio is 1.0200

1.02