# Question: The scores on a standardized mathematics test for 8th grade children

The scores on a standardized mathematics test for 8th-grade children in New York State form a normal distribution with a mean of µ = 70 and a standard deviation of σ = 10.

a. What proportion of the students in the state have scores less than X = 75?

b. If samples of n = 4 are selected from the population, what proportion of the samples will have means less than µ = 75?

c. If samples of n = 25 are selected from the population, what proportion of the samples will have means less than µ = 75?

a. What proportion of the students in the state have scores less than X = 75?

b. If samples of n = 4 are selected from the population, what proportion of the samples will have means less than µ = 75?

c. If samples of n = 25 are selected from the population, what proportion of the samples will have means less than µ = 75?

## Answer to relevant Questions

A normal distribution has a mean of µ = 54 and a standard deviation of σ = 6. a. What is the probability of randomly selecting a score less than X = 51? b. What is the probability of selecting a sample of n = 4 scores with ...A sample is selected from a population with a mean of µ = 40 and a standard deviation of σ = 8. a. If the sample has n = 4 scores, what is the expected value of µ and the standard error of M? b. If the sample has n = 16 ...For a population with a standard deviation of σ = 20, how large a sample is necessary to have a standard error that is: a. less than or equal to = points? b. less than or equal to 2 points? c. less than or equal to 1 point? Researchers at a National Weather Center in the northeastern United States recorded the number of 90° days each year since records first started in 1875. The numbers form a normal shaped distribution with a mean of µ = 9.6 ...Although there is a popular belief that herbal remedies such as Ginkgo biloba and Ginseng may improve learning and memory in healthy adults, these effects are usually not supported by well-controlled research (Persson, ...Post your question