Probability

There are 130 NRICH Mathematical resources connected to Probability
Trick or Treat
problem

Trick or treat

Age
7 to 11
Challenge level
filled star filled star empty star
Mrs. Smith had emptied packets of chocolate-covered mice, plastic frogs and gummi-worms into a cauldron for treats. What treat is Trixie most likely to pick out?
A Bit of a Dicey problem
problem

A bit of a dicey problem

Age
7 to 11
Challenge level
filled star filled star filled star
When you throw two regular, six-faced dice you have more chance of getting one particular result than any other. What result would that be? Why is this?
The wrong stats
problem

The wrong stats

Age
16 to 18
Challenge level
filled star empty star empty star
Why MUST these statistical statements probably be at least a little bit wrong?
Gambling at Monte Carlo
problem

Gambling at monte carlo

Age
14 to 16
Challenge level
filled star filled star filled star
A man went to Monte Carlo to try and make his fortune. Is his strategy a winning one?
396
problem

396

Age
14 to 16
Challenge level
filled star empty star empty star
The four digits 5, 6, 7 and 8 are put at random in the spaces of the number : 3 _ 1 _ 4 _ 0 _ 9 2 Calculate the probability that the answer will be a multiple of 396.
Succession in Randomia
problem

Succession in randomia

Age
16 to 18
Challenge level
filled star empty star empty star
By tossing a coin one of three princes is chosen to be the next King of Randomia. Does each prince have an equal chance of taking the throne?
Winning the Lottery
problem

Winning the lottery

Age
7 to 11
Challenge level
filled star filled star empty star
Find out about the lottery that is played in a far-away land. What is the chance of winning?
Marbles and Bags
problem

Marbles and bags

Age
14 to 16
Challenge level
filled star filled star empty star
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?
How Many Balls?
problem

How many balls?

Age
16 to 18
Challenge level
filled star empty star empty star
A bag contains red and blue balls. You are told the probabilities of drawing certain combinations of balls. Find how many red and how many blue balls there are in the bag.
Heavy hydrocarbons
problem

Heavy hydrocarbons

Age
14 to 18
Challenge level
filled star filled star empty star
Explore the distribution of molecular masses for various hydrocarbons