People are selected to serve on juries by randomly picking names from the list o

Question

People are selected to serve on juries by randomly picking names from the list of registered voters. The average age for registered voters in the county is ? = 44.3 years with a standard deviation of ? = 12.4. A statistician computes the average age for a group of n = 12 people currently serving on a jury and obtains a mean of M = 36.6 years.

A)What is the expected value for the mean of the sampling distribution of all possible juries? (Report answer to 1 decimal place.)

B)What is the standard error of of the mean for the sampling distribution of all possible juries? (Report answer to 2 decimal places.)

C)How likely is it to obtain a random sample of n = 12 jurors with an average age equal to or less than 36.6? (Report proportion to 4 decimal places or percentage to 2 decimal places.)

D)This score would be considered a(n) (representative/extreme) score because the value of it's z-score is (Report answer to 2 decimal places.)

Explanation / Answer

A)e expected value for the mean =44.3

b)

standard error of of the mean= standard deviation/sqrt(n)=12.4/sqrt(12)=3.58

c)

P(X<36.6)=P(Z<(36.6-44.3)/3.58)=P(Z<-2.15)=0.0158

d)

This score would be considered a extreme score because the value of it's z-score is less than -2.

Related Questions

Navigate

• Browse (All)
• Browse P
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.