Suppose the preliteracy scores of three-year-old students in the
United States are normally distributed. Shelia, a...
Suppose the preliteracy scores of three-year-old students in the
United States are normally distributed. Shelia, a preschool
teacher, wants to estimate the mean score on preliteracy tests for
the population of three-year-olds. She draws a simple random sample
of 20 students from her class of three-year-olds and records their
preliteracy scores (in points).
74,79,83,85,88,90,94,95,95,97,99,99,100,103,105,105,106,107,107,108
Calculate the sample mean (?⎯⎯⎯x¯), sample standard deviation
(?s), and standard error (SE) of the students' scores. Round your
answers to four decimal places.
Determine the...
The value of mortgage loans made by a certain bank one year were
normally distributed with...
The value of mortgage loans made by a certain bank one year were
normally distributed with a mean of $120,000 and a standard
deviation of $40,000. What is the probability that a randomly
selected mortgage loan was in the range of $40,000 to $200,000?
(Round your answer to 4 decimal places).[
A standardized exam's scores are normally distributed. In a
recent year, the mean test score was...
A standardized exam's scores are normally distributed. In a
recent year, the mean test score was 1540 and the standard
deviation was 314.
The test scores of four students selected at random are 1970,
1290, 2270, and 1430.
Find the z-scores that correspond to each value and determine
whether any of the values are unusual.