Hypothesis Testing — Unit test Answers

The set of life spans of an appliance is normally distributed with a mean = 48 months and a standard deviation = 8 months. What is the life span of an appliance that has a z-score of –3?

The graph below shows the amount of time Misha spent outside over a 30-day period. How might the graph be considered misleading?

Laila guesses on all 20 questions of a multiple-choice test. Each question has 4 answer choices. What is the probability of a success and a failure for this experiment?

Voluntary sampling is one type of sampling method that is not probability based. This means that

Which set of population data is the least dispersed from its mean?

What is the formula for margin of error?

Johnni guessed on all 8 questions of a multiple-choice quiz. Each question has 4 answer choices. What is the probability that she got exactly 3 questions correct? Round the answer to the nearest thousandth.

The life spans of a computer manufacturer’s hard drives are normally distributed, with a mean of 3 years 6 months and a standard deviation of 9 months. What is the probability of a randomly selected hard drive from the company lasting between 2 years 3 months and 3 years 3 months? Use the portion of the standard normal table below to help answer the question.zProbability0.000.50000.230.59100.330.62930.670.74861.000.84131.330.90821.670.95252.000.9772

A gymnastics coach records the scores of a gymnast and develops the probability distribution below. What is the probability the gymnast scores a 9 or 9.5?Probability DistributionGymnastics Score: XProbability: P(X)50.025.50.0260.066.50.170.167.50.1480.188.50.189?9.50.02

The number of absences for one week for all students at a high school were compiled, and the probability distribution below was created. What is the probability in any given week that a randomly selected student will be absent no more than one day?Probability DistributionDays Absent: XProbability: P(X)00.7810.1420.0330.014050.04

A supervisor finds the mean number of miles that the employees in a department live from work. He finds and . Which statement must be true?

Miguel Cabrera has had 369 at bats, and he has 127 hits and 21 home runs. (Note: The home runs are included in the hits data.) If he is challenged to a batting battle, what is the expected score of each at bat if he earns 1 point for each hit that is not a home run and 5 points for each home run?