Other tags that relate to Eight Dominoes
Factors and multiples. Multiplication & division. Dominoes. Mathematical reasoning & proof. Integers. Selecting and using information. Symmetry. Addition & subtraction. Place value. Working systematically.There are 154 results
Broad Topics > Properties of Numbers > Factors and multiples
X Marks the Spot
Age 11 to 14
Challenge Level
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" .
Times Right
Age 11 to 16
Challenge Level
Using the digits 1, 2, 3, 4, 5, 6, 7 and 8, mulitply a two two digit numbers are multiplied to give a four digit number, so that the expression is correct. How many different solutions can you find?
What Do You Need?
Age 7 to 11
Challenge Level
Four of these clues are needed to find the chosen number on this grid and four are true but do nothing to help in finding the number. Can you sort out the clues and find the number?
American Billions
Age 11 to 14
Challenge Level
Play the divisibility game to create numbers in which the first two digits make a number divisible by 2, the first three digits make a number divisible by 3...
Making Pathways
Age 7 to 11
Challenge Level
Can you find different ways of creating paths using these paving slabs?
The Remainders Game
Age 7 to 14
Challenge Level
Play this game and see if you can figure out the computer's chosen number.
Multiplication Series: Number Arrays
Age 5 to 11
This article for teachers describes how number arrays can be a useful representation for many number concepts.
Divisively So
Age 11 to 14
Challenge Level
How many numbers less than 1000 are NOT divisible by either: a) 2 or 5; or b) 2, 5 or 7?
Missing Multipliers
Age 7 to 14
Challenge Level
What is the smallest number of answers you need to reveal in order to work out the missing headers?
Funny Factorisation
Age 11 to 16
Challenge Level
Using the digits 1 to 9, the number 4396 can be written as the product of two numbers. Can you find the factors?
Eminit
Age 11 to 14
Challenge Level
The number 8888...88M9999...99 is divisible by 7 and it starts with the digit 8 repeated 50 times and ends with the digit 9 repeated 50 times. What is the value of the digit M?
Adding All Nine
Age 11 to 14
Challenge Level
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. . . .
Thirty Six Exactly
Age 11 to 14
Challenge Level
The number 12 = 2^2 × 3 has 6 factors. What is the smallest natural number with exactly 36 factors?
Big Powers
Age 11 to 16
Challenge Level
Three people chose this as a favourite problem. It is the sort of problem that needs thinking time - but once the connection is made it gives access to many similar ideas.
Multiples Sudoku
Age 11 to 14
Challenge Level
Each clue in this Sudoku is the product of the two numbers in adjacent cells.
Just Repeat
Age 11 to 14
Challenge Level
Think of any three-digit number. Repeat the digits. The 6-digit number that you end up with is divisible by 91. Is this a coincidence?
Remainders
Age 7 to 14
Challenge Level
I'm thinking of a number. My number is both a multiple of 5 and a multiple of 6. What could my number be?
Gabriel's Problem
Age 11 to 14
Challenge Level
Gabriel multiplied together some numbers and then erased them. Can you figure out where each number was?
AB Search
Age 11 to 14 Short
Challenge Level
The five digit number A679B, in base ten, is divisible by 72. What are the values of A and B?
Product Sudoku
Age 11 to 16
Challenge Level
The clues for this Sudoku are the product of the numbers in adjacent squares.
Repeaters
Age 11 to 14
Challenge Level
Choose any 3 digits and make a 6 digit number by repeating the 3 digits in the same order (e.g. 594594). Explain why whatever digits you choose the number will always be divisible by 7, 11 and 13.
Oh! Hidden Inside?
Age 11 to 14
Challenge Level
Find the number which has 8 divisors, such that the product of the divisors is 331776.
A First Product Sudoku
Age 11 to 14
Challenge Level
Given the products of adjacent cells, can you complete this Sudoku?
Inclusion Exclusion
Age 11 to 14
Challenge Level
How many integers between 1 and 1200 are NOT multiples of any of the numbers 2, 3 or 5?
Crossings
Age 7 to 11
Challenge Level
In this problem we are looking at sets of parallel sticks that cross each other. What is the least number of crossings you can make? And the greatest?
Ben's Game
Age 11 to 16
Challenge Level
Ben, Jack and Emma passed counters to each other and ended with the same number of counters. How many did they start with?
Even So
Age 11 to 14
Challenge Level
Find some triples of whole numbers a, b and c such that a^2 + b^2 + c^2 is a multiple of 4. Is it necessarily the case that a, b and c must all be even? If so, can you explain why?
Factoring Factorials
Age 11 to 14
Challenge Level
Find the highest power of 11 that will divide into 1000! exactly.
Scoring with Dice
Age 7 to 11
Challenge Level
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?
Money Measure
Age 7 to 11
Challenge Level
How can you use just one weighing to find out which box contains the lighter ten coins out of the ten boxes?
Being Resilient - Primary Number
Age 5 to 11
Challenge Level
Number problems at primary level that may require resilience.
Flow Chart
Age 11 to 14
Challenge Level
The flow chart requires two numbers, M and N. Select several values for M and try to establish what the flow chart does.
Can You Find a Perfect Number?
Age 7 to 14
Can you find any perfect numbers? Read this article to find out more...
Hot Pursuit
Age 11 to 14
Challenge Level
I added together the first 'n' positive integers and found that my answer was a 3 digit number in which all the digits were the same...
Number Tracks
Age 7 to 11
Challenge Level
Ben’s class were cutting up number tracks. First they cut them into twos and added up the numbers on each piece. What patterns could they see?
Which Is Quicker?
Age 7 to 11
Challenge Level
Which is quicker, counting up to 30 in ones or counting up to 300 in tens? Why?
Odds and Threes
Age 7 to 11
Challenge Level
A game for 2 people using a pack of cards Turn over 2 cards and try to make an odd number or a multiple of 3.
Alison's Quilt
Age 11 to 14
Challenge Level
Nine squares are fitted together to form a rectangle. Can you find its dimensions?
Being Collaborative - Primary Number
Age 5 to 11
Challenge Level
Number problems at primary level to work on with others.
Transposition Cipher
Age 11 to 16
Challenge Level
Can you work out what size grid you need to read our secret message?
Satisfying Statements
Age 11 to 14
Challenge Level
Can you find any two-digit numbers that satisfy all of these statements?
Always, Sometimes or Never? Number
Age 7 to 11
Challenge Level
Are these statements always true, sometimes true or never true?
Give Me Four Clues
Age 7 to 11
Challenge Level
Four of these clues are needed to find the chosen number on this grid and four are true but do nothing to help in finding the number. Can you sort out the clues and find the number?
Multiply Multiples 3
Age 7 to 11
Challenge Level
Have a go at balancing this equation. Can you find different ways of doing it?
Multiply Multiples 2
Age 7 to 11
Challenge Level
Can you work out some different ways to balance this equation?
Multiply Multiples 1
Age 7 to 11
Challenge Level
Can you complete this calculation by filling in the missing numbers? In how many different ways can you do it?
What Numbers Can We Make Now?
Age 11 to 14
Challenge Level
Imagine we have four bags containing numbers from a sequence. What numbers can we make now?
Three Neighbours
Age 7 to 11
Challenge Level
Look at three 'next door neighbours' amongst the counting numbers. Add them together. What do you notice?
NRICH is part of the family of activities in the Millennium Mathematics Project.