Answer:
Explanation:
To calculate the mean, add all the numbers together, then divide the sum of all values in a data set by the number of values.
Given :-

Add all the numbers:-
- 17 + 9 + 19 + 18 + 12
- = 75
Now, divide 75 by the number of values in the data, which is (5):-
Therefore, the mean is 15.
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