What would be recommended CPA of 2nd Campaign?
I got this tricky question in one of my recent interview.
Please explain how to solve!!!
Q. Account has 4 campaigns with CPA of 50$, 78$, 101$, 23$. You have to bring down the CPA by 20% for campaigns with the CPA higher than the avg CPA. What would be recommended CPA of 2nd campaign?
Re: What would be recommended CPA of 2nd Campaign?
The average CPA's can only be added and averaged out if there are the same number of conversions in each campaign - or am I missing something....
If, for example, there is one conversion in each of the first 3 campaigns, and 1,000 conversions in the 4th then the average CPA will be close to $23
So my answer would have to be that you cannot work this out without knowing the conversion volumes. The CPA is already an average - simply working the average of the averages do not give you the true average cost of your conversions.
I could try and elaborate on the maths but my brain is hurting already....