Hockey Stick Identity - Yr 11+. WORK IN PROGRESS - MESSY!
How many numbers have this property? - Yr 5+. Divisibility by 5 test, familiarity with counting/arrangements.
Number square - Yr 7+. Knowledge of averages leads to one possible approach, but not necessary - can be solved with basic reasoning.
Dice problem - symmetry shortcut - Yr 7+. Best to have some familiarity with dice problems already.
Symmetry vs counting outcomes - Yr 7+. Nice introduction to symmetry techniques by way of comparison with basic methods. Dice problem.
Jellybean problem - Yr 7+. With/without replacement.
Scheduling problem - Yr 7+. Factorial notation nice but not necessary.
Pigeonhole principle problems - Yr 7+.
Frog puzzle - Yr 7+. Knowledge of the coordinate grid and basic probability.
Probability that a product is positive? - Yr 7+.
3 perspectives on a seating problem - Yr 7+. Familiarity with seating problems helpful, factorial notation nice but not necessary. Example of symmetry technique.
A variety of problems - Yr 7+. Basic probability, expected value, some involve algebra.
Another collection of quick questions - Yr 7+.
The Principle of Inclusion/Exclusion questions - Yr 7+. Some require algebra.
What's the probability that if we pick 4 points on a grid at random they will make a rectangle? - Yr 7+.
Mostly expected value plus some quick questions on other topics - Yr 7+. Variety of questions from easy to tough.
How many triangles can we make? - Yr 7+.
Sum of the 5-digit palindromes - Yr 7+. Multi-part.
Probability that a sum is divisible by 3 - Yr 7+. Familiar with mod helps.
Length questions - Yr 7+. Probability that a point falls within a certain interval.
Area questions - Yr 8+. Probability that point/s fall within a certain area.
Arrival times - Yr 9+. Requires coordinate geometry.
Coordinate geometry probability questions - Yr 9+. Probability that a point is within a certain region of the plane.
Odd or even? - Yr 9+.
Location in the plane - Yr 9+. Probability of being closer to one point than another.
Arranging books - Yr 10+. Factorial notation helpful. Best to have some familiarity with simpler arrangement problems.
Seating plan question - Yr 10+. Factorial notation helpful. Best to have some familiarity with simpler arrangement problems.
Probability of a point being inside a region - Yr 10+. Area of a circle, circles in the coordinate plane.
Grid problems - Yr 10+. How many possible paths through a grid?
Somewhat unusual nC4r problems - Yr 10+.
Picking squares on a grid - Yr 10+. Knowledge nCr notation.
Two probability questions - Yr 10+. 1: nCr notation, binomial distribution. 2: dice and coins problem.
Problem using the method of 1-1 correspondences - Yr 11+. Uses nCr notation.
Distributing n items to k boxes - Yr 11+. Uses nCr notation.
Variety of tricky probability questions - Yr 11+.
Problems using Fibonacci - Yr 11+.Return to main page