Given that n=10, ∑(x-120)=20 . ∑(x-120)^2=200 . Find mean and standard deviation of X
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0
Answer:
4
Step-by-step explanation:
Answered by
2
Answer: Mean = 122
Let d = x - 120,
hence x̄ = 120 + ∑d/n = 122.
S.D = 4
Step-by-step explanation: n=10, Σxi=20, Σxi²=200
we know S.D = √Σxi²/n - (Σxi/n)²
= √200/10 - (20/10)²
= √20 - (20/10)²
= √20 - 400/100 ______(both zeros get cancel)
soo √20-4
= √16
= 4
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