Scores on an entrance exam in a large university, freshman course are normally distributed with mean 72.5 and standard deviation 13.0. Find the probability that the score X on a randomly selected exam paper is between 70 and 80. Find the probability that the mean score X̅ of 40 randomly selected exam papers is between 70 and 80.

Scores on an entrance exam in a large university, freshman course are normally distributed with mean 72.5 and standard deviation 13.0. Find the probability that the score X on a randomly selected exam paper is between 70 and 80. Find the probability that the mean score X̅ of 40 randomly selected exam papers is between 70 and 80.

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

See similar textbooks

Similar questions

The golf scores for a school team were normally distributed with a mean of 68 and a standard deviation of three.Find the probability that a golfer scored between 66 and 70
Assume that adults have IQ scores that are normally distributed with a mean of 98 and standard deviation of 15. Find the probability that a randomly selected adult has an IQ greater than 104.
The amount of time spent by customers in a store follows a normal distribution with a mean of 30 minutes and a standard deviation of 5 minutes. What is the probability that a randomly selected customer spends between 25 and 35 minutes in the store? The IQ scores of a population follow a normal distribution with a mean of 100 and a standard deviation of 15. What percentage of the population has an IQ score between 85 and 115?
The manufacturer of cans of salmon that are supposed to have a net weight of 6 ounces tells you that the net weight is actually a normal random variable with a mean of 6.23 ounces and a standard deviation of 0.24 ounce. Suppose that you draw a random sample of 43 cans. Find the probability that the mean weight of the sample is less than 6.22 ounces. Probability =
The average age of the JYP employees is known to be 32 years and the standard deviation is 5 years. Find the probability that a random sample of 36 employees will have an average age of less than 30 years. What is the probability of 36 employees who have an average age of less than 30 years?
In a recent year, grade 7 Maryland State public school students taking a mathematics assessment test had a mean score of 230 with a standard deviation of 23. Assume the scores are normally distributed. Find the probability that a student had a score higher than 285.
Alfie Solomons owns a rum distillery. On average, he produces 100 liters of rum with a standard deviation of 18 liters. What is the probability of producing an average of 90 liters of rum or more over the course of 9 days?
IQ scores are normally distributed with a mean of 100 and standard devation of 15. find the probability of having an IQ between 136 and 142.
Assume that adults have IQ scores that are normally distributed with a mean of 103.9 and a standard deviation of 16.5. Find the probability that a randomly selected adult has an IQ greater than 132.4
The average height of women is 64 inches. The standard deviation is 2 inches. The heights have a normal distribution. Find the probability that a randomly selected woman is shorter 59 inches or taller than 68 inches.
A student's chances of being accepted to Harvard are about 5%. What is the probability that only three students from the same school will be accepted if twenty apply? Calculate the expected number of accepted students if there were ten applicants from the same school. Also, find the standard deviation of the number of accepted applicants.
Most graduate of Senior High Schools are taking up Batangas State University College Entrance Exam. Scores on the entrance exam are roughly normally distributed with a mean of 527 and a standard deviation of 112. What is the probability of an individual scoring above 500 on the entrance exam? how high must an individual score on the entrance exam in order to score in the highest 5%?