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For younger learners

  • Early Years Foundation Stage

Visualising - Short Problems

This is part of our collection of Short Problems.

You may also be interested in our longer problems on Visualising.

Folded A4

Age 11 to 14
ShortChallenge Level Yellow star

What shapes can be made by folding an A4 sheet of paper only once?

Squares in a Square

Age 11 to 14
ShortChallenge Level Yellow star

In the diagram, the small squares are all the same size. What fraction of the large square is shaded?

Painted Octahedron

Age 11 to 14
ShortChallenge Level Yellow star

What is the smallest number of colours needed to paint the faces of a regular octahedron so that no adjacent faces are the same colour?

Potatoes

Age 11 to 14
ShortChallenge Level Yellow star

Weekly Problem 19 - 2009
When I looked at the greengrocer's window I saw a sign. When I went in and looked from the other side, what did I see?

Soma Surface

Age 11 to 14
ShortChallenge Level Yellow star

What is the surface area of the solid shown?

Daniel's Star

Age 11 to 14
ShortChallenge Level Yellow star

A solid 'star' shape is created. How many faces does it have?

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?

Bishop's Paradise

Age 11 to 14
ShortChallenge Level Yellow star

Weekly Problem 37 - 2013
Which of the statements about diagonals of polygons is false?

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?

Blockupied

Age 11 to 14
ShortChallenge Level Yellow starYellow star

A 1x2x3 block is placed on an 8x8 board and rolled several times.... How many squares has it occupied altogether?

Adjacent Factors

Age 11 to 14
ShortChallenge Level Yellow starYellow star

Two numbers can be placed adjacent if one of them divides the other. Using only $1,...,10$, can you write the longest such list?

Same Face

Age 11 to 14
ShortChallenge Level Yellow starYellow star

A cube is rolled on a plane, landing on the squares in the order shown. Which two positions had the same face of the cube touching the surface?

Semaphore

Age 11 to 14
ShortChallenge Level Yellow starYellow star

I am standing behind five pupils who are signalling a five-digit number to someone on the opposite side of the playground. What number is actually being signalled?

Reflected Back

Age 11 to 14
ShortChallenge Level Yellow starYellow star

Imagine reflecting the letter P in all three sides of a triangle in turn. What is the final result?

Integral Polygons

Age 11 to 14
ShortChallenge Level Yellow starYellow star

Each interior angle of a particular polygon is an obtuse angle which is a whole number of degrees. What is the greatest number of sides the polygon could have?

Turning N Over

Age 11 to 14
ShortChallenge Level Yellow starYellow star

A card with the letter N on it is rotated through two different axes. What does the card look like at the end?

Reading from Behind

Age 11 to 14
ShortChallenge Level Yellow starYellow star

Can you find the time between 3 o'clock and 10 o'clock when my digital clock looks the same from both the front and back?

Doubly Symmetric

Age 11 to 14
ShortChallenge Level Yellow starYellow star

What is the smallest number of additional squares that must be shaded so that this figure has at least one line of symmetry and rotational symmetry of order 2?

Kangaroo Hops

Age 11 to 14
ShortChallenge Level Yellow starYellow starYellow star

Weekly Problem 11 - 2011
Kanga hops ten times in one of four directions. At how many different points can he end up?

Hexagon Cut Out

Age 11 to 14
ShortChallenge Level Yellow starYellow starYellow star

Weekly Problem 52 - 2012
An irregular hexagon can be made by cutting the corners off an equilateral triangle. How can an identical hexagon be made by cutting the corners off a different equilateral triangle?

Crawl Around the Cube

Age 11 to 14
ShortChallenge Level Yellow starYellow starYellow star

Weekly Problem 37 - 2010
An ant is crawling around the edges of a cube. From the description of his path, can you predict when he will return to his starting point?

Hamiltonian Cube

Age 11 to 16
ShortChallenge Level Yellow starYellow star

Weekly Problem 36 - 2007
Find the length along the shortest path passing through certain points on the cube.

Dicey Directions

Age 14 to 16
ShortChallenge Level Yellow star

An ordinary die is placed on a horizontal table with the '1' face facing East... In which direction is the '1' face facing after this sequence of moves?

Out of the Window

Age 14 to 16
ShortChallenge Level Yellow star

Find out how many pieces of hardboard of differing sizes can fit through a rectangular window.

Rectangle Rearrangement

Age 14 to 16
ShortChallenge Level Yellow star

A 3x8 rectangle is cut into two pieces... then rearranged to form a right-angled triangle. What is the perimeter of the triangle formed?

Semicircular Design

Age 14 to 16
ShortChallenge Level Yellow star

Weekly Problem 9 - 2016
The diagram to the right shows a logo made from semi-circular arcs. What fraction of the logo is shaded?

Twelve Cubed

Age 14 to 16
ShortChallenge Level Yellow star

A wooden cube with edges of length 12cm is cut into cubes with edges of length 1cm. What is the total length of the all the edges of these centimetre cubes?

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?

Cubic Covering

Age 14 to 16
ShortChallenge Level Yellow starYellow star

A blue cube has blue cubes glued on all of its faces. Yellow cubes are then glued onto all the visible blue facces. How many yellow cubes are needed?

Folding in Half

Age 14 to 16
ShortChallenge Level Yellow starYellow star

How does the perimeter change when we fold this isosceles triangle in half?

Painted Purple

Age 14 to 16
ShortChallenge Level Yellow starYellow star

Three faces of a $3 \times 3$ cube are painted red, and the other three are painted blue. How many of the 27 smaller cubes have at least one red and at least one blue face?

Trisected Triangle

Age 14 to 16
ShortChallenge Level Yellow starYellow star

Weekly Problem 34 - 2015
Four tiles are given. For which of them can three be placed together to form an equilateral triangle?

Facial Sums

Age 14 to 16
ShortChallenge Level Yellow starYellow star

Can you make the numbers around each face of this solid add up to the same total?

Tied Up

Age 14 to 16
ShortChallenge Level Yellow starYellow star

How much of the field can the animals graze?

Centre Square

Age 14 to 16
ShortChallenge Level Yellow starYellow starYellow star

What does Pythagoras' Theorem tell you about the radius of these circles?

In or Out?

Age 14 to 16
ShortChallenge Level Yellow starYellow starYellow star

Weekly Problem 52 - 2014
Four arcs are drawn in a circle to create a shaded area. What fraction of the area of the circle is shaded?

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Seven Squares - Group-worthy Task

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?

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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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