A) A study of elephants wishes to determine the average weight of a certain subspecies of...

A) A study of elephants wishes to determine the average weight of a certain subspecies of elephants. The standard deviation of the population is 500 pounds. How many elephants need to be weighed so that we can be 95% confident to be accurate within 200 pounds?

B) TRUE OR FALSE: The confidence level of an interval estimate of a parameter is the probability that the interval estimate is one that will contain the parameter.

C) A report states that 42% of home owners had a vegetable garden. How large a sample is needed to estimate the true proportion of home owners who have vegetable gardens to within 6% with 95% confidence?

Solutions

Expert Solution

Refer Z-table or use excel function "=NORM.S.INV((1-0.025))" to find the Z-value.

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The confidence level is expressed as a percentage or a probability, that a specified interval will contain the population parameter.

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Refer Z-table or use excel function "=NORM.S.INV((1-0.025))" to find the Z-value.

orchestra answered 1 year ago

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