Question 1180863
12 * 1.25 ^ x is correct.
at 0 years from the present, the value is 12 * 1.25 ^ 0 = 12
at 1 year from the present, the value is 12 * 1.25 ^ 1 = 15
at 2 years from the present, the value is 12 * 1.25 ^ 2 = 18.75
etc.....