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Number and algebra

  • The Number System and Place Value
  • Calculations and Numerical Methods
  • Fractions, Decimals, Percentages, Ratio and Proportion
  • Properties of Numbers
  • Patterns, Sequences and Structure
  • Algebraic expressions, equations and formulae
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Geometry and measure

  • Angles, Polygons, and Geometrical Proof
  • 3D Geometry, Shape and Space
  • Measuring and calculating with units
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  • Pythagoras and Trigonometry
  • Vectors and Matrices

Probability and statistics

  • Handling, Processing and Representing Data
  • Probability

Working mathematically

  • Thinking mathematically
  • Developing positive attitudes
  • Cross-curricular contexts

Advanced mathematics

  • Decision Mathematics and Combinatorics
  • Advanced Probability and Statistics
  • Mechanics
  • Calculus

For younger learners

  • Early Years Foundation Stage

Patterns and Sequences Short Problems

Pattern Snake

Age 11 to 14
ShortChallenge Level Yellow starYellow star

This pattern repeats every 12 dots. Can you work out what a later piece will be?

What a Coincidence!

Age 11 to 14
ShortChallenge Level Yellow star

Consider two arithmetic sequences: 1998, 2005, 2012,... and 1996, 2005, 2014,... Which numbers will appear in both?

Suit Sequence

Age 11 to 14
ShortChallenge Level Yellow star

A pattern repeats every six symbols. What are the 100th and 101st symbols?

Knights and Knaves

Age 11 to 14
ShortChallenge Level Yellow starYellow starYellow star

Knights always tell the truth. Knaves always lie. Can you catch these knights and knaves out?

Doubly Consecutive Sums

Age 11 to 14
ShortChallenge Level Yellow starYellow starYellow star

How many numbers less than 2017 are both the sum of two consecutive integers and the sum of five consecutive integers?

Expanding Pattern

Age 11 to 14
ShortChallenge Level Yellow star

How many squares are needed to continue this pattern?

Fibonacci Deduction

Age 11 to 14
ShortChallenge Level Yellow star

Leonard writes down a sequence of numbers. Can you find a formula to predict the seventh number in his sequence?

Hexagon Line

Age 11 to 14
ShortChallenge Level Yellow starYellow star

How many hexagons are required for the perimeter of the whole shape to have length 1002cm?

Street Lamps

Age 11 to 14
ShortChallenge Level Yellow star

Walking up a steep hill, I pass 10 equally spaced street lamps. How long do I take to walk from the first lamp to the last?

Fruit Line-up

Age 11 to 14
ShortChallenge Level Yellow star

This grocer wants to arrange his fruit in a particular order, can you help him?

Triangular Clock

Age 11 to 14
ShortChallenge Level Yellow star

Trinni rearanges numbers on a clock face so each adjacent pair add up to a triangle number... What number did she put where 6 would usually be?

Printing Error

Age 11 to 14
ShortChallenge Level Yellow star

Every third page number in this book has been omitted. Can you work out what number will be on the last page?

Sliding Robot

Age 11 to 14
ShortChallenge Level Yellow starYellow star

A robot moves along the number line. Where will it be after 2011 slides?

Many Matildas

Age 11 to 14
ShortChallenge Level Yellow star

MatildaMatildaMatil... What is the 1000th letter?

How Many Rectangles?

Age 11 to 14
ShortChallenge Level Yellow starYellow star

By drawing 5 horizontal and four vertical lines, one can form 12 rectangles. What is the greatest number of rectangles that can be formed by drawing 15 lines?

Night Watchmen

Age 11 to 14
ShortChallenge Level Yellow starYellow star

Grannie's watch gains 30 minutes every hour, whilst Grandpa's watch loses 30 minutes every hour. What is the correct time when their watches next agree?

Knockdown

Age 11 to 14
ShortChallenge Level Yellow starYellow star

Weekly Problem 51 - 2016
Pegs numbered 1 to 50 are placed in a row. Alternate pegs are knocked down, and this process is repeated. What is the number of the last peg to be knocked down?

Collatz 13

Age 14 to 16
ShortChallenge Level Yellow starYellow star

If a number is even, halve it; if odd, treble it and add 1. If a sequence starts at 13, what will be the value of the 2008th term?

12345

Age 14 to 16
ShortChallenge Level Yellow starYellow star

Repeat a pattern of numbers to form a larger number. Can you find the sum of all the digits?

Collatz-ish

Age 14 to 16
ShortChallenge Level Yellow starYellow star

A sequence is generated using these rules. For which values of n is the nth term equal to n?

Below 400

Age 14 to 16
ShortChallenge Level Yellow starYellow star

Can you work out which number will appear directly below 400 in this pattern?

Trolley Park

Age 14 to 16
ShortChallenge Level Yellow starYellow star

In a supermarket, there are two lines of tightly packed trolleys. What is the length of one trolley?

Alternating Sum

Age 14 to 16
ShortChallenge Level Yellow starYellow star

Given that the number 2008 is the correct answer to a sum, can you find n?

Newspaper Sheets

Age 14 to 16
ShortChallenge Level Yellow starYellow star

From only the page numbers on one sheet of newspaper, can you work out how many sheets there are altogether?

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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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