Answer:
Impossible to determine a pattern
Explanation:
A pattern requires multiple data points to determine, and since you are only given one, this is not possible. However, if you assume that the total amount of time that you exercise must remain the same, then you can simply subtract 15 by the running minutes to get the walking
3 12
6 9
9 6
12 3
15 0
Depending on the scenario of the problem, you can determine if this assumption was valid.