Can you work out the arrangement of the digits in the square so that the given products are correct? The numbers 1 - 9 may be used once and once only.
Can you use this information to work out Charlie's house number?
Arrange the four number cards on the grid, according to the rules, to make a diagonal, vertical or horizontal line.
I throw three dice and get 5, 3 and 2. Add the scores on the three dice. What do you get? Now multiply the scores. What do you notice?
What is the lowest number which always leaves a remainder of 1 when divided by each of the numbers from 2 to 10?
Explore patterns based on a rhombus. How can you enlarge the pattern - or explode it?
What is the remainder when 2^2002 is divided by 7? What happens with different powers of 2?
A garrison of 600 men has just enough bread ... but, with the news that the enemy was planning an attack... How many ounces of bread a day must each man in the garrison be allowed, to hold out 45. . . .
A mathematician goes into a supermarket and buys four items. Using a calculator she multiplies the cost instead of adding them. How can her answer be the same as the total at the till?
When the number x 1 x x x is multiplied by 417 this gives the answer 9 x x x 0 5 7. Find the missing digits, each of which is represented by an "x" .
Learn how to use advanced pasting techniques to create interactive spreadsheets.
Learn how to use increment buttons and scroll bars to create interactive Excel resources.
Learn how to make a simple table using Excel.
Investigate factors and multiples using this interactive Excel spreadsheet. Use the increment buttons for experimentation and feedback.
This investigation uses Excel to optimise a characteristic of interest.
This article for teachers describes how modelling number properties involving multiplication using an array of objects not only allows children to represent their thinking with concrete materials, but it can also assist them in forming useful mental pictures to support memory and reasoning.