5.2 The Uniform Distribution
A flat density over an interval, probabilities read as rectangle areas, percentiles solved back from those areas, and conditional questions on a shortened interval.
17 exercises
5.2 Exercise 13
The distribution can be written as X ~ U(1.5, 4.5).
In this distribution, outcomes are equally likely. What does this mean?
5.2 Exercise 15
The distribution can be written as X ~ U(1.5, 4.5).
What are the constraints for the values of x?
5.2 Exercise 17
The distribution can be written as X ~ U(1.5, 4.5).
What is P(2 < x < 3)?
5.2 Exercise 19
The distribution can be written as X ~ U(1.5, 4.5).
What is P(x = 1.5)?
5.2 Exercise 21
The distribution can be written as X ~ U(1.5, 4.5).
Find the probability that a randomly selected home has more than 3,000 square feet given that you already know the house has more than 2,000 square feet.
5.2 Exercise 23
Use the following information to answer the next eight exercises. A distribution is given as X ~ U(0, 12).
What is b? What does it represent?
5.2 Exercise 25
Use the following information to answer the next eight exercises. A distribution is given as X ~ U(0, 12).
What is the theoretical mean?
5.2 Exercise 29
Use the following information to answer the next eight exercises. A distribution is given as X ~ U(0, 12).
Find the 40th percentile.
5.2 Exercise 31
Use the following information to answer the next eleven exercises. The age of cars in the staff parking lot of a suburban college is uniformly distributed from six months (0.5 years) to 9.5 years.
In words, define the random variable X.
5.2 Exercise 33
Use the following information to answer the next eleven exercises. The age of cars in the staff parking lot of a suburban college is uniformly distributed from six months (0.5 years) to 9.5 years.
The interval of values for x is ______.
5.2 Exercise 35
Use the following information to answer the next eleven exercises. The age of cars in the staff parking lot of a suburban college is uniformly distributed from six months (0.5 years) to 9.5 years.
Write the probability density function.
5.2 Exercise 37
Use the following information to answer the next eleven exercises. The age of cars in the staff parking lot of a suburban college is uniformly distributed from six months (0.5 years) to 9.5 years.
Find the average age of the cars in the lot.
5.2 Exercise 43
For each probability and percentile problem, draw the picture.
A random number generator picks a number from one to nine in a uniform manner.
- X ~ _________
- Graph the probability distribution.
- f(x) = _________
- μ = _________
- σ = _________
- P(3.5 < x < 7.25) = _________
- P(x > 5.67)
- P(x > 5|x > 3) = _________
- Find the 90th percentile.
5.2 Exercise 45
For each probability and percentile problem, draw the picture.
A subway train arrives every eight minutes during rush hour. We are interested in the length of time a commuter must wait for a train to arrive. The time follows a uniform distribution.
- Define the random variable. X = _______
- X ~ _______
- Graph the probability distribution.
- f(x) = _______
- μ = _______
- σ = _______
- Find the probability that…
5.2 Exercise 47
Use the following information to answer the next three exercises. The Sky Train from the terminal to the rental–car and long–term parking center is supposed to arrive every eight minutes. The waiting times for the train are known to follow a uniform distribution.
What is the average waiting time (in minutes)?
- zero
- two
- three
- four
5.2 Exercise 49
Use the following information to answer the next three exercises. The Sky Train from the terminal to the rental–car and long–term parking center is supposed to arrive every eight minutes. The waiting times for the train are known to follow a uniform distribution.
The probability of waiting more than seven minutes given a person has waited more than four minutes is?
- 0.125
- 0.25
- 0.5
- 0.75
5.2 Exercise 53
Use the following information to answer the next three exercises. The Sky Train from the terminal to the rental–car and long–term parking center is supposed to arrive every eight minutes. The waiting times for the train are known to follow a uniform distribution.
The number of miles driven by a truck driver falls between 300 and 700, and follows a uniform distribution.
- Find the probability that t…
Adapted from Introductory Statistics 2e © 2023 Rice University. Licensed under CC BY 4.0. Source: Introductory Statistics 2e. Imported at revision 50ec917.