Q:
# What Is a 90 Percent Confidence Interval?

A confidence interval is an interval of numbers that contains the expected true value of the population parameter that the interval addresses. A 90 percent confidence interval indicates a 90 percent confidence level that the true value is located within the given parameters.

Continue ReadingInformation from a sample population is used to compute the endpoints of the interval. A large population consists of a sample size of observations that is greater than 30. For example, a sample of 121 observations with a standard deviation of 20 and an average of 50 has a 90 percent confidence interval for the true population average.

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Q:
## What Does "mean" Stand for in Math?

A: The "mean" in math refers to the average value of a set of numbers. It is calculated by adding all the numbers in a set and then dividing that sum by the t... Full Answer >Filed Under: -
Q:
## What Is the Mode of a Set of Numbers?

A: The mode of a set of numbers is the value which occurs the most often in the set. For example, the mode of {1, 2, 3, 2, 4} is 2, since it occurs twice. Full Answer >Filed Under: -
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## What Is the "median" in Math?

A: In mathematics, the median value is the middle number in a set of sorted numbers. For example, in the set of numbers 10, 11, 13, 15, 16, 23 and 26, the med... Full Answer >Filed Under: -
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## What Does "average" Mean in Mathematics?

A: In mathematics, the “average” typically refers to the “mean value” of a set of numbers that is found by adding all the numbers in the set and then dividing... Full Answer >Filed Under: