Thread: Distribution of sample average

Suppose Y(bar) is the average of n observations from a population with SD (σ) = 2.5.
a. For n = 25, what is P(| Y(bar) - μ| < 0.1)? (.1586)
b. For n = 100, what is P(|Y(bar) - μ| < 0.1)? (.3108)
c. Which answer (3a or 3b) is probably more accurate? Why?
d. (Statistics). How large a sample is needed so that P(|Y(bar) - μ| < 0.1) ≥ .99?

Originally Posted by ShaunW

Suppose Y(bar) is the average of n observations from a population with SD (σ) = 2.5.
a. For n = 25, what is P(| Y(bar) - μ| < 0.1)? (.1586)
b. For n = 100, what is P(|Y(bar) - μ| < 0.1)? (.3108)
c. Which answer (3a or 3b) is probably more accurate? Why?
d. (Statistics). How large a sample is needed so that P(|Y(bar) - μ| < 0.1) ≥ .99?

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