<h3>
Answer: It increases by 1</h3>
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Explanation:
To compute the mean, we first add up the numbers
5+3+5+3+4 = 20
Then divide by 5 since there are 5 numbers in the set
20/5 = 4
The mean is 4.
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Now replace one of the '3's with 8 and recompute the mean
5+8+5+3+4 = 25
25/5 = 5
The mean is now 5.
The old mean in the previous section was 4.
The mean has increased by 1 since 5-4 = 1.
Side note: The increase from 3 to 8 is +5, which when dividing by 5, we're basically incrementing the mean by +1.