Conjecturing and generalising

There are 405 NRICH Mathematical resources connected to Conjecturing and generalising
Converging Means
problem

Converging means

Age
14 to 16
Challenge level
filled star filled star empty star
Take any two positive numbers. Calculate the arithmetic and geometric means. Repeat the calculations to generate a sequence of arithmetic means and geometric means. Make a note of what happens to the two sequences.
Squares, Squares and More Squares
problem

Squares, squares and more squares

Age
11 to 14
Challenge level
filled star empty star empty star
Can you dissect a square into: 4, 7, 10, 13... other squares? 6, 9, 12, 15... other squares? 8, 11, 14... other squares?
Tourism
problem

Tourism

Age
11 to 14
Challenge level
filled star filled star filled star
If you can copy a network without lifting your pen off the paper and without drawing any line twice, then it is traversable. Decide which of these diagrams are traversable.
Absurdity Again
problem

Absurdity again

Age
16 to 18
Challenge level
filled star empty star empty star
What is the value of the integers a and b where sqrt(8-4sqrt3) = sqrt a - sqrt b?
Hypotenuse Lattice points
problem

Hypotenuse lattice points

Age
14 to 16
Challenge level
filled star filled star filled star
The triangle OMN has vertices on the axes with whole number co-ordinates. How many points with whole number coordinates are there on the hypotenuse MN?
Chocolate Maths
problem

Chocolate maths

Age
11 to 14
Challenge level
filled star empty star empty star
Pick the number of times a week that you eat chocolate. This number must be more than one but less than ten. Multiply this number by 2. Add 5 (for Sunday). Multiply by 50... Can you explain why it works?
Dotty triangles
problem

Dotty triangles

Age
11 to 14
Challenge level
filled star empty star empty star
Imagine an infinitely large sheet of square dotty paper on which you can draw triangles of any size you wish (providing each vertex is on a dot). What areas is it/is it not possible to draw?
The Bridges of Konigsberg
problem

The bridges of konigsberg

Age
11 to 18
Challenge level
filled star empty star empty star
Investigate how networks can be used to solve a problem for the 18th Century inhabitants of Konigsberg.
Move a Match
problem

Move a match

Age
7 to 11
Challenge level
filled star filled star empty star
How can you arrange these 10 matches in four piles so that when you move one match from three of the piles into the fourth, you end up with the same arrangement?
Simple Train Journeys
problem

Simple train journeys

Age
5 to 11
Challenge level
filled star empty star empty star
How many different journeys could you make if you were going to visit four stations in this network? How about if there were five stations? Can you predict the number of journeys for seven stations?