To find the constant of proportionality (unit rate) of d to s, we just need to use the equation d = 15s and divide the two sides of the equation by s, so we will have:
d = 15s
d/s = 15s/s
d/s = 15
So this is the value of the constant, and what is means is the velocity of the wolf: the amount of distance it will travel for each second.
If the constant is equal to 15 meters per second, it means that for each second the wolf travels using this constant, it will travel 15 meters.
The constant of proportionality is the number at wich the two variables relate. In this case for every second running the wolf will travel a distance of 15 m, this means that if two seconds have passed the wolf will have travelled a distance of 30m and so on. So we can assume that the constant for this question is 15.
