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Question
Find the mean of: all prime numbers upto 30
Solution
The all prime numbers upto 30 are 2, 3, 5, 7, 11, 13, 17, 19, 23, 29
∴Sum of these observations = 2 + 3 +5 + 7+ 11 + 13 + 17 + 19 + 23 +29 = 129
and, number of their observations = 10
∴ Required mean = `129/10 = 12.9`
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