Answer:
The correct answer is 20%
Step-by-step explanation:
Considering that I need to set up a weighted forecasting system over the three month period and the weights are represented as a percentage.
And the weights of the most recent months are the same, and each of those weights is double what the oldest month. we can exemplify the solution by this simple equation
40% + 40% + 20% = 100%
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Each percentage is one of three months.