Other tags that relate to X-dice
Random variables. Spreadsheets. Probability. Tree diagrams. Combining probabilities. Experimental probability. Interactivities. Conditional probability. Theoretical probability. Mathematical modelling.There are 21 results
Broad Topics > Probability > Combining probabilities
Marbles and Bags
Age 14 to 16 Challenge Level:
Two bags contain different numbers of red and blue marbles. A marble is removed from one of the bags. The marble is blue. What is the probability that it was removed from bag A?
The Better Bet
Age 14 to 16 Challenge Level:
Here are two games you have to pay to play. Which is the better bet?
Same Number!
Age 14 to 16 Challenge Level:
If everyone in your class picked a number from 1 to 225, do you think any two people would pick the same number?
Gambling at Monte Carlo
Age 14 to 16 Challenge Level:
A man went to Monte Carlo to try and make his fortune. Is his strategy a winning one?
Win or Lose?
Age 14 to 16 Challenge Level:
A gambler bets half the money in his pocket on the toss of a coin, winning an equal amount for a head and losing his money if the result is a tail. After 2n plays he has won exactly n times. Has. . . .
Fixing the Odds
Age 14 to 16 Challenge Level:
You have two bags, four red balls and four white balls. You must put all the balls in the bags although you are allowed to have one bag empty. How should you distribute the balls between the two. . . .
Taking Chances Extended
Age 14 to 18
This article, for students and teachers, is mainly about probability, the mathematical way of looking at random chance.
Odd Dice
Age 14 to 16 Short Challenge Level:
These strange dice are rolled. What is the probability that the sum obtained is an odd number?
How Risky Is My Diet?
Age 11 to 16 Challenge Level:
Newspapers said that eating a bacon sandwich every day raises the risk of bowel cancer by 20%. Should you be concerned?
Statins and Risk
Age 14 to 16 Challenge Level:
"Statins cut the risks of heart attacks and strokes by 40%"
Should the Professor take statins? Can you help him decide?
Knock-out
Age 16 to 18 Challenge Level:
Before a knockout tournament with 2^n players I pick two players. What is the probability that they have to play against each other at some point in the tournament?
Put Out
Age 16 to 18 Challenge Level:
After transferring balls back and forth between two bags the probability of selecting a green ball from bag 2 is 3/5. How many green balls were in bag 2 at the outset?
Squash
Age 16 to 18 Challenge Level:
If the score is 8-8 do I have more chance of winning if the winner is the first to reach 9 points or the first to reach 10 points?
Dicey Decisions
Age 16 to 18 Challenge Level:
Can you devise a fair scoring system when dice land edge-up or corner-up?
Voting Paradox
Age 14 to 18 Challenge Level:
Some relationships are transitive, such as `if A>B and B>C then it follows that A>C', but some are not. In a voting system, if A beats B and B beats C should we expect A to beat C?
Snooker Frames
Age 16 to 18 Challenge Level:
It is believed that weaker snooker players have a better chance of winning matches over eleven frames (i.e. first to win 6 frames) than they do over fifteen frames. Is this true?
Snooker
Age 16 to 18 Challenge Level:
A player has probability 0.4 of winning a single game. What is his probability of winning a 'best of 15 games' tournament?
Lottery Simulator
Age 7 to 16 Challenge Level:
Use this animation to experiment with lotteries. Choose how many balls to match, how many are in the carousel, and how many draws to make at once.
Do You Brush Your Teeth Every Day?
Age 14 to 18 Challenge Level:
How can we find out answers to questions like this if people often lie?
Heavy Hydrocarbons
Age 14 to 18 Challenge Level:
Explore the distribution of molecular masses for various hydrocarbons
Molecular Sequencer
Age 14 to 18 Challenge Level:
Investigate the molecular masses in this sequence of molecules and deduce which molecule has been analysed in the mass spectrometer.
NRICH is part of the family of activities in the Millennium Mathematics Project.