Author Archives: hangtime

Mean & Expected Value of Binomial Distributions

This video covers the basic formula that quickly spits out the mean, a.k.a. "expected value", of a binomial distribution. Flipping coins or rolling dice, this formula quickly tells you how many heads or 5's you'd expect to get on average from n trials.

This video appears on the page: Binomial Probability Calculations

Binomial Probability Using Your Calculator

This video covers another batch of binomial probability word problems, but this time we use a calculator to do the fancy combinatorics stuff because the numbers are way too big to handle doing factorials by hand.

This video appears on the page: Binomial Probability Calculations

Binomial Probability Calculations Using Formula

This video is pretty long, but that's a good thing because it's so full of awesome examples! Plus it takes a long time to cancel all those crazy factorials (exclamation points). Whether you're in Stats, Algebra or Discrete Math, if you're in a section that has anything to do with "binomial probability" -- or if you just honestly happen to wonder what the probability is of getting between 5 and 7 heads if you flip a coin exactly 13 times -- this video is for you!

This video appears on the page: Binomial Probability Calculations

Binomial Probability Distribution Vocab

This video covers what all those letters in the Binomial Probability Theorem mean, from the p's and q's, to the x's and n's, to that giant backwards-E-looking thing they call Sigma. Also covered are what these problems mean by "success" and "failure" and "trials".

This video appears on the page: Binomial Probability Calculations

Tips for When to Use Binomial Probability Formula

This video covers some really important tips for how to solve binomial probability distribution word problems, starting with how to know which problems you should be doing this to in the first place! Also covered are tricky situations where you have to use the formula a few times for "or more" type problems, as in "if you flip a coin 5 times, what is the probability of getting 3 OR MORE heads?"

This video appears on the page: Binomial Probability Calculations

Binomial Probability Calculations:
Tips for When to Use Binomial Probability Formula
Binomial Probability Distribution Vocab
Binomial Probability Calculations Using Formula
Binomial Probability Using Your Calculator
Mean & Expected Value of Binomial Distributions
Variance & Standard Deviation of Binomial Distributions
Usual vs Unusual Events For Binomial Distribution

These videos cover everything you'll need to know to do binomial probability distribution problems -- stuff like "If you flip a coin 7 times, what are the chances of getting exactly 5 heads?" The hardest part of these problems is knowing which problems to use the binomial formula on, and then knowing what numbers to plug in where. These formulas all have both p's and q's in them.

Part of the course(s): Statistics

"0+" Probability

This video explains a weird number that some math teachers like to use when talking about very small probabilities, instead of having to write "a really really tiny number" all the time.

This video appears on the page: Discrete Probability Distributions: Mean, Variance, Standard Deviation, Expected Value

Probability Distribution vs Histogram

This short video aims to clear up a common confusion: What's the difference between a distribution and a histogram?

This video appears on the page: Discrete Probability Distributions: Mean, Variance, Standard Deviation, Expected Value

Calculating Variance & Standard Deviation of Probability Distribution

This video explains how to find the variance and standard deviation of a probability distribution when you are given a table of outcomes and their corresponding probabilities, such as for survey results or a weighted coin.

This video appears on the page: Discrete Probability Distributions: Mean, Variance, Standard Deviation, Expected Value

Calculating Mean of Probability Distribution

This video explains how to find the mean (average) of a probability distribution when you are given a table of outcomes and their corresponding probabilities, such as for survey results or a weighted coin.

This video appears on the page: Discrete Probability Distributions: Mean, Variance, Standard Deviation, Expected Value

Parameters of Discrete Probability Distributions:
Calculating Mean of Probability Distribution
Calculating Variance & Standard Deviation of Probability Distribution
Probability Distribution vs Histogram
"0+" Probability
Expected Value & E-Commerce 101

These videos cover formulas to find the various parameters of a discrete probability distribution when you're given a contingency table of outcomes and probabilities. If you're working with a specific type of distribution -- Binomial, Poisson, etc -- check out those chapters instead.

Part of the course(s): Statistics

The 3 Rules of Probability Distributions

This video covers a very common type of problem that's in every Stats textbook I've ever seen, where they give you a table and ask you "is this a probability distribution". You're supposed to figure it out using the three rules.

This video appears on the page: Intro to Probability Distributions

Discrete vs Continuous Random Variables

This video explains what a "random variable" is in Stats, as well as the difference between discrete and continuous random variables. In Stats class, you're almost always using discrete variables when doing probability problems.

This video appears on the page: Intro to Probability Distributions

Intro to Probability Distributions:
Discrete vs Continuous,
3 Rules of Probability Distributions

Once you've already learned about basic probability, this chapter takes things in a more Stats-heavy direction by introducing the vocab of probability "distributions", and covers the 3 rules that every probability distribution must follow.

Part of the course(s): Statistics

Study Tips from ThatTutorGuy

Get inspired and get tips that will help you rock your next math or science test! Some of the videos contain stories of Chris's most successful tutoring clients, stories that will inspire you and give you actionable techniques that helped those students overcome math anxiety. Other videos will give you detailed, step-by-step methods you can use to do your homework more effectively, study smarter for tests, and coast into the final on a cushion of well-earned math excellence.

Calculating Dependent & Conditional Probabilities

This chapter covers problems where you're supposed to find the probability of one thing "given" something else. Definitely check out the contingency tables videos because they are your best friend for dependent probability problems in statistics. Even if it's a word problem, cook up your own contingency table, it's safer than plug-and-chug!

This video appears on the page: Calculating Dependent & Conditional Probabilities ,Free Sample Videos ,statistics free videos

Dependent & Conditional Probabilities

This chapter covers problems where you're supposed to find the probability of one thing "given that" something else has already happened. For example, in a political survey, you may be given survey results in a contingency table and asked, "What is the proportion of respondents who intend to vote for Candidate A given that they said they are Republican."

Part of the course(s): Statistics

Hybrid Multiplication & Addition Rule Problems

Often in probability word problems, you're going to need a combination of these two rules because outcome probabilities that you calculate with the multiplication rule have to be added up to get the overall probability of a compound event. Things like rolling even numbers in dice, or flipping some combination of heads and tails.

This video appears on the page: The Multiplication Rule of Probability

5% Fudge Rule for Multiplication Rule

This is a quick video explaining when you're allowed to sort of pretend that dependent events -- such as drawings "without replacement" -- are "close enough" to independent that you can do the math as if they're independent. Hint: the cutoff is around 5 percent.

This video appears on the page: The Multiplication Rule of Probability

The Multiplication Rule of Probability ("AND")

This video covers the multiplication rule for probability which is used in "and" problems, such as the probability of rolling two dice and getting a 5 "and" a 6, or flipping two coins and getting a head "and" a tails. (As the name implies, multiplication is involved.)

This video appears on the page: The Multiplication Rule of Probability