Conjecturing and generalising

There are 405 NRICH Mathematical resources connected to Conjecturing and generalising
Number Tracks
problem

Number tracks

Age
7 to 11
Challenge level
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Ben's class were cutting up number tracks. First they cut them into twos and added up the numbers on each piece. What patterns could they see?
Tables Without Tens
problem

Tables without tens

Age
7 to 11
Challenge level
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Investigate and explain the patterns that you see from recording just the units digits of numbers in the times tables.
Loopy
problem

Loopy

Age
14 to 16
Challenge level
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Investigate sequences given by $a_n = \frac{1+a_{n-1}}{a_{n-2}}$ for different choices of the first two terms. Make a conjecture about the behaviour of these sequences. Can you prove your conjecture?
Lower Bound
problem

Lower bound

Age
14 to 16
Challenge level
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What would you get if you continued this sequence of fraction sums? 1/2 + 2/1 = 2/3 + 3/2 = 3/4 + 4/3 =
Dicing with numbers
problem

Dicing with numbers

Age
11 to 14
Challenge level
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In how many ways can you arrange three dice side by side on a surface so that the sum of the numbers on each of the four faces (top, bottom, front and back) is equal?
Chocolate 2010
problem

Chocolate 2010

Age
14 to 16
Challenge level
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First of all, pick the number of times a week that you would like to eat chocolate. Multiply this number by 2...
Fit These Shapes
problem

Fit these shapes

Age
5 to 11
Challenge level
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What is the largest number of circles we can fit into the frame without them overlapping? How do you know? What will happen if you try the other shapes?
Pinned Squares
problem

Pinned squares

Age
14 to 16
Challenge level
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What is the total number of squares that can be made on a 5 by 5 geoboard?
AMGM
problem

Amgm

Age
14 to 16
Challenge level
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Can you use the diagram to prove the AM-GM inequality?
Broken Toaster
problem

Broken toaster

Age
7 to 11
Challenge level
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Only one side of a two-slice toaster is working. What is the quickest way to toast both sides of three slices of bread?