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प्रश्न
Find the mean of: first five odd natural numbers
उत्तर
The first five odd natural numbers are = 1, 3, 5, 7, 9
∴ Sum of these observations =1 + 3 + 5 + 7 + 9 = 25
and, number of their observations = 5
∴ Required mean = `25/5 = 5`
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