Answer: The mean change in the forecasted high temperatures is of 4.33 degrees.
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* The mean of a data-set is given by the sum of it's observations, divided by the number of observations.
* There are 7 days, thus, there will be 6 changes.
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* From Tuesday to Wednesday, the change is of |87 - 87| = 0.
* Following this logic, the changes are of 6, 5, 3, 6, 6.
* Thus, the average change will be of:
The average change in the forecasted high temperatures is of 4.33 degrees.
Explanation: