A consumer price analyst claims that prices for liquid crystal display (LCD) computer monitors have a...

A consumer price analyst claims that prices for liquid crystal display (LCD) computer monitors have a mean of $ 170 and a standard deviation of $ 47.

2. You randomly selected 25 LCD compute monitors. What is the probability that their mean cost is less than $ 180? Assume here that the prices are normally distributed

3. You randomly selected 64 LCD compute monitors. What is the probability that their mean cost is less than $ 180?

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Expert Solution

Solution :

= / n = 47 / 25 = 9.4

P( < 180) = P(( - ) / < (180 - 170) / 9.4)

= P(z < 1.064)

= 0.8563

Probability = 0.8563

= / n = 47 / 64 = 5.875

P( < 180) = P(( - ) / < (180 - 170) / 5.875)

= P(z < 1.702)

= 0.9556

Probability = 0.9556

orchestra answered 1 year ago

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