Question

If x represents a random variable with mean 147 and standard
deviation 45, then the standard deviation of the sampling
distribution of the means with sample size 81 is 5.

- True
- False

Answer #1

Solution :

Given that,

mean = = 147

standard deviation = = 45

n = 81

_{}
= 147

_{}
=
/
n = 45 /
81 = **5**

**True**

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