Q.1 What is the mean, standard devia... [FREE SOLUTION]

In order for the sums of distribution to approach a normal distribution, what must be true?

What is the mean of ΣX?

Four friends, Janice, Barbara, Kathy and Roberta, decided to carpool together to get to school. Each day the driver would be chosen by randomly selecting one of the four names. They carpool to school for $96$ days. Use the normal approximation to the binomial to calculate the following probabilities. Round the standard deviation to four decimal places.

a. Find the probability that Janice is the driver at most $20$ days.

b. Find the probability that Roberta is the driver more than $16$ days.

c. Find the probability that Barbara drives exactly $24$ of those $96$ days.

NeverReady batteries has engineered a newer, longer lasting AAA battery. The company claims this battery has an average life span of $17$ hours with a standard deviation of $0.8$ hours. Your statistics class questions this claim. As a class, you randomly select $30$ batteries and find that the sample mean life span is $16.7$ hours. If the process is working properly, what is the probability of getting a random sample of $30$ batteries in which the sample mean lifetime is $16.7$ hours or less? Is the company’s claim reasonable?

Use the following information to answer the next six exercises: Yoonie is a personnel manager in a large corporation. Each month she must review 16 of the employees. From past experience, she has found that the reviews take her approximately four hours each to do with a population standard deviation of $1.2$ hours. Let $X$ be the random variable representing the time it takes her to complete one review. Assume $X$ is normally distributed. Let $X$ be the random variable representing the mean time to complete the 16 reviews. Assume that the 16 reviews represent a random set of reviews.

1. What is the mean, standard deviation, and sample size?

Find Study Materials for

Create Study Materials

Select your language

Introductory Statistics

Answers without the blur.

Short Answer

What is the mean, standard deviation, and sample size?

Step by Step Solution

Step 1: Given information

Step 2: Explanation

Step 3: Final answer

Most popular questions for Math Textbooks

Want to see more solutions like these?

Recommended explanations on Math Textbooks

Select your language

Introductory Statistics

Answers without the blur.

Short Answer

What is the mean, standard deviation, and sample size?

Step by Step Solution

Step 1: Given information

Step 2: Explanation

Step 3: Final answer

Most popular questions for Math Textbooks

Want to see more solutions like these?

Recommended explanations on Math Textbooks

Decision Maths

Calculus

Probability and Statistics

Statistics

Mechanics Maths

Geometry

Pure Maths