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Can you explain the strategy for winning this game with any target?

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Is it possible to rearrange the numbers 1,2......12 around a clock face in such a way that every two numbers in adjacent positions differ by any of 3, 4 or 5 hours?

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We start with one yellow cube and build around it to make a 3x3x3 cube with red cubes. Then we build around that red cube with blue cubes and so on. How many cubes of each colour have we used?

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Do you notice anything about the solutions when you add and/or subtract consecutive negative numbers?

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Got It game for an adult and child. How can you play so that you know you will always win?

This article gives you a few ideas for understanding the Got It! game and how you might find a winning strategy.

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Try entering different sets of numbers in the number pyramids. How does the total at the top change?

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If you take a three by three square on a 1-10 addition square and multiply the diagonally opposite numbers together, what is the difference between these products. Why?

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Can you find six numbers to go in the Daisy from which you can make all the numbers from 1 to a number bigger than 25?

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Charlie has made a Magic V. Can you use his example to make some more? And how about Magic Ls, Ns and Ws?

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By selecting digits for an addition grid, what targets can you make?

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How many solutions can you find to this sum? Each of the different letters stands for a different number.

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This Sudoku requires you to do some working backwards before working forwards.

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Delight your friends with this cunning trick! Can you explain how it works?

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15 = 7 + 8 and 10 = 1 + 2 + 3 + 4. Can you say which numbers can be expressed as the sum of two or more consecutive integers?

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Here is a chance to play a version of the classic Countdown Game.

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Different combinations of the weights available allow you to make different totals. Which totals can you make?

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The country Sixtania prints postage stamps with only three values 6 lucres, 10 lucres and 15 lucres (where the currency is in lucres).Which values cannot be made up with combinations of these postage. . . .

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This Sudoku, based on differences. Using the one clue number can you find the solution?

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Use the differences to find the solution to this Sudoku.

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Five numbers added together in pairs produce: 0, 2, 4, 4, 6, 8, 9, 11, 13, 15 What are the five numbers?

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Choose any three by three square of dates on a calendar page...

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Crosses can be drawn on number grids of various sizes. What do you notice when you add opposite ends?

This article explains how to make your own magic square to mark a special occasion with the special date of your choice on the top line.

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Special clue numbers related to the difference between numbers in two adjacent cells and values of the stars in the "constellation" make this a doubly interesting problem.

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Make your own double-sided magic square. But can you complete both sides once you've made the pieces?

Find out about Magic Squares in this article written for students. Why are they magic?!

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A cinema has 100 seats. Show how it is possible to sell exactly 100 tickets and take exactly Â£100 if the prices are Â£10 for adults, 50p for pensioners and 10p for children.

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Ann thought of 5 numbers and told Bob all the sums that could be made by adding the numbers in pairs. The list of sums is 6, 7, 8, 8, 9, 9, 10,10, 11, 12. Help Bob to find out which numbers Ann was. . . .

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Find the values of the nine letters in the sum: FOOT + BALL = GAME

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The letters in the following addition sum represent the digits 1 ... 9. If A=3 and D=2, what number is represented by "CAYLEY"?

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Here is a chance to play a fractions version of the classic Countdown Game.

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Fancy a game of cricket? Here is a mathematical version you can play indoors without breaking any windows.

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In the following sum the letters A, B, C, D, E and F stand for six distinct digits. Find all the ways of replacing the letters with digits so that the arithmetic is correct.

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Investigate the different ways that fifteen schools could have given money in a charity fundraiser.

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In this 100 square, look at the green square which contains the numbers 2, 3, 12 and 13. What is the sum of the numbers that are diagonally opposite each other? What do you notice?

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What happens when you add a three digit number to its reverse?

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How many ways can you find to put in operation signs (+ - x Ã·) to make 100?

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There are nasty versions of this dice game but we'll start with the nice ones...

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Try out some calculations. Are you surprised by the results?

This article suggests some ways of making sense of calculations involving positive and negative numbers.

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Some Games That May Be Nice or Nasty for an adult and child. Use your knowledge of place value to beat your opponent.

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You have four jugs of 9, 7, 4 and 2 litres capacity. The 9 litre jug is full of wine, the others are empty. Can you divide the wine into three equal quantities?

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Make a set of numbers that use all the digits from 1 to 9, once and once only. Add them up. The result is divisible by 9. Add each of the digits in the new number. What is their sum? Now try some. . . .

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What is the sum of all the digits in all the integers from one to one million?