4.1. Standard Distributions http://www.ck12.org
4.1 Standard Distributions
Learning Objectives
- Be familiar with the standard distributions (normal, binomial, and exponential).
- Use standard distributions to solve for events in problems in which the distribution belongs to those families.
Say you were buying a new bicycle for going back and forth to school. You want to buy something that lasts a long
time and something with parts that will also last a long time. You research on the internet and find one brand “Buy
Me Bike” that shows the following graph with all of its advertising.
(a) What type of probability distribution is being represented by this graph?
(b) Is the data represented continuous or discrete? How can you tell?
(c) Does the data in the graph indicate that the company produces bicycles that have a respectable life span? Explain.
Work through the lesson and then revisit this problem to determine the solution.
Now that we know a little about probability and variables, let’s move into the concept of distribution. A distribution
is simply the description of the possible values of the random variables and the possible occurrences of these. For
our discussions, we will say it is the probability of the occurrences. The main form of probability distribution is
standard distribution.Standard distributionis a normal distribution and often people refer to it as abell curve.
If you were to toss a fair coin 100 times, you would expect the coin to land on tails close to 50 times and heads 50
times. However, tails may not appear as expected. Look at the histograms below.