If Deliah does jumping jacks at a constant rate, this means that she does them at the same pace or you could say that she does the same amount of jumping jacks in a specified amount of time, ie. if you counted how many jumping jacks she did in one minute, it would be same as how many she would complete in the next minute, and the next, and so on.
Now given that she does 184 jumping jacks in four minutes, and she has kept a constant pace throughout, to find out how many she does each minute, we simply need to divide the number of jumping jacks she does in 4 minutes by 4. Thus:
Jumping jacks in 1 minute = Jumping jacks in 4 minutes / 4
= 184 / 4
= 46
Thus, Deliah can do 46 jumping jacks per minute.
First, let's make these two into equations.
The first plan has an initial fee of $40 and costs an additional $0.16 per mile driven.
Our equation would then be
C = 40 + 0.16m
where C is the total cost, and m is the number of miles driven.
The second plan has an initial fee of $51 and costs an additional $0.11 per mile driven.
So, the equation is
C = 51 + 0.11m
where C is the total cost, and m is the number of miles driven.
Now, your question seems to be asking for one mileage for both, equalling one cost. I would go through all the steps I've taken to try and find this for you, but it would probably take hours to type out and read. In short, I'm not entirely sure that an answer like that is possible in this situation, simply because of the large difference in the initial fee of the two plans, along with the sparse common multiples between the two mileage costs.