# Question

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?

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