Arithmetic sequences

There are 50 NRICH Mathematical resources connected to Arithmetic sequences
100 Square Jigsaw
problem

100 Square Jigsaw

Age
5 to 7
Challenge level
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Can you complete this jigsaw of the 100 square?
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.
Squares in rectangles
problem

Squares in rectangles

Age
11 to 14
Challenge level
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A 2 by 3 rectangle contains 8 squares and a 3 by 4 rectangle contains 20 squares. What size rectangle(s) contain(s) exactly 100 squares? Can you find them all?
Coordinate Patterns
problem

Coordinate Patterns

Age
11 to 14
Challenge level
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Charlie and Alison have been drawing patterns on coordinate grids. Can you picture where the patterns lead?
Seven Squares - Group-worthy Task
problem

Seven Squares - Group-worthy Task

Age
11 to 14
Challenge level
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Choose a couple of the sequences. Try to picture how to make the next, and the next, and the next... Can you describe your reasoning?
More Number Pyramids
problem

More Number Pyramids

Age
11 to 14
Challenge level
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When number pyramids have a sequence on the bottom layer, some interesting patterns emerge...
Squares, Squares and More Squares
problem

Squares, Squares and More Squares

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

Polite Numbers

Age
16 to 18
Challenge level
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A polite number can be written as the sum of two or more consecutive positive integers, for example 8+9+10=27 is a polite number. Can you find some more polite, and impolite, numbers?
Cherries Come in Twos
problem

Cherries Come in Twos

Age
7 to 11
Challenge level
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Susie took cherries out of a bowl by following a certain pattern. How many cherries had there been in the bowl to start with if she was left with 14 single ones?
Six in a Circle
problem

Six in a Circle

Age
5 to 7
Challenge level
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If there is a ring of six chairs and thirty children must either sit on a chair or stand behind one, how many children will be behind each chair?