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probability in the
3D and higher
Browse Middle School Probability
Stars indicate particularly interesting answers or
good places to begin browsing.
See also Middle School Statistics.
Selected answers to common questions:
- Probability That a Sum Is Divisible by Three [11/04/2009]
How many ways can you choose three numbers from 1-100 whose sum is
divisible by three?
- Probability Tree Diagrams [8/22/1996]
What are the odds that two children will both be boys, firing once will
hit a target, cargoes will arrive ruined?
- Randomly Selecting a Card [02/20/1998]
What is the probability that a card randomly selected from a standard
deck will be a king and a club?
- Rolling a Number Cube [02/27/2002]
A number cube is labeled with the numbers 3,6,9,12,15,and 18. Describe an
outcome of rolling the cube that has a probability of 3/6.
- Socks [8/31/1996]
Jack's sock drawer contains 10 blue socks and 12 gray socks. The room is
dark and he cannot turn on the light...
- Sum of Two Dice [12/05/2001]
Find the probabilities of rolling different sums.
- Teaching Elementary Probability [10/07/1998]
If you toss a number cube 20 times, could it land on six 20 times?
- Theoretical and Experimental Probability [05/07/2001]
If we spin a spinner 20 times and record the results, what might we
conclude from our experiment?
- Three Heads in a Row [01/25/2001]
How many flips of a coin on the average will it take to get three heads
(or tails) in a row?
- Tossing a Coin and Rolling a Die [11/14/2002]
If you toss a coin and roll a die, what is the probability of
obtaining: a) heads and a five b) heads or a five c) tails or a two?
- Understanding Probability [05/13/2002]
If I were looking for a probability of colored marbles in three
packages, how would I do that?
- Using Tables to Find Probabilities [10/23/2003]
Levi has 3 blue shirts and 1 red shirt. He has 1 pair of white slacks
and 1 pair of blue slacks. What is the probability that he will wear
white slacks and a blue shirt?
- What Is N Factorial Used For? [08/29/2001]
I have heard that it is used in probability, but what for, and how?
- What is the Meaning of "Average"? [03/28/2007]
An interesting conversation that defines the general concepts of
average and central tendency, and looks at the usefulness of such
measures both in representing the data and for making predictions
about future events.
- What Makes Events Independent? [06/03/2002]
Why, after tossing 10 heads in a row, isn't the next toss more likely
to come up tails?
- Why Do We Multiply the Probabilities of Independent Events? [10/15/2009]
We learned the probability formula P(A and B) = P(A) x P(B). Why do we
multiply the two probabilities rather than adding them?
- Why Learn about Probability and Statistics? [04/17/2002]
Why is probability so important to learn? When will we use it in the
- The World Series [10/22/2000]
What is the probability of the Yankees and the Mets playing each other in
the World Series?
- Years That Start on Sunday [10/02/2000]
What is the probability that a randomly chosen year will start on a
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