This activity focuses on doubling multiples of five.
Take the number 6 469 693 230 and divide it by the first ten prime
numbers and you'll find the most beautiful, most magic of all
numbers. What is it?
Use this grid to shade the numbers in the way described. Which
numbers do you have left? Do you know what they are called?
The clockmaker's wife cut up his birthday cake to look like a clock
face. Can you work out who received each piece?
On a calculator, make 15 by using only the 2 key and any of the
four operations keys. How many ways can you find to do it?
What is the lowest number which always leaves a remainder of 1 when
divided by each of the numbers from 2 to 10?
All the girls would like a puzzle each for Christmas and all the
boys would like a book each. Solve the riddle to find out how many
puzzles and books Santa left.
On Friday the magic plant was only 2 centimetres tall. Every day it
doubled its height. How tall was it on Monday?
56 406 is the product of two consecutive numbers. What are these
Using the numbers 1, 2, 3, 4 and 5 once and only once, and the
operations x and ÷ once and only once, what is the smallest
whole number you can make?
Can you see how these factor-multiple chains work? Find the chain which contains the smallest possible numbers. How about the largest possible numbers?
Put operations signs between the numbers 3 4 5 6 to make the highest possible number and lowest possible number.
Look on the back of any modern book and you will find an ISBN code. Take this code and calculate this sum in the way shown. Can you see what the answers always have in common?
This article for teachers looks at how teachers can use problems from the NRICH site to help them teach division.
Can you order the digits from 1-3 to make a number which is divisible by 3 so when the last digit is removed it becomes a 2-figure number divisible by 2, and so on?
The Scot, John Napier, invented these strips about 400 years ago to
help calculate multiplication and division. Can you work out how to
use Napier's bones to find the answer to these multiplications?
Use your logical-thinking skills to deduce how much Dan's crisps and ice-cream cost altogether.
Can you work out what a ziffle is on the planet Zargon?
Here are the prices for 1st and 2nd class mail within the UK. You have an unlimited number of each of these stamps. Which stamps would you need to post a parcel weighing 825g?
There are four equal weights on one side of the scale and an apple
on the other side. What can you say that is true about the apple
and the weights from the picture?
This multiplication uses each of the digits 0 - 9 once and once only. Using the information given, can you replace the stars in the calculation with figures?
What is happening at each box in these machines?
Four Go game for an adult and child. Will you be the first to have four numbers in a row on the number line?
Grandma found her pie balanced on the scale with two weights and a
quarter of a pie. So how heavy was each pie?
Chandrika was practising a long distance run. Can you work out how
long the race was from the information?
This task combines spatial awareness with addition and multiplication.
Work out Tom's number from the answers he gives his friend. He will
only answer 'yes' or 'no'.
Can you work out how many flowers there will be on the Amazing Splitting Plant after it has been growing for six weeks?
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?
Can you arrange 5 different digits (from 0 - 9) in the cross in the
There were 22 legs creeping across the web. How many flies? How many spiders?
EWWNP means Exploring Wild and Wonderful Number Patterns Created by Yourself! Investigate what happens if we create number patterns using some simple rules.
Claire thinks she has the most sports cards in her album. "I have
12 pages with 2 cards on each page", says Claire. Ross counts his
cards. "No! I have 3 cards on each of my pages and there are. . . .
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.
Find the next number in this pattern: 3, 7, 19, 55 ...
What do you notice about the date 03.06.09? Or 08.01.09? This
challenge invites you to investigate some interesting dates
Amy has a box containing domino pieces but she does not think it is a complete set. She has 24 dominoes in her box and there are 125 spots on them altogether. Which of her domino pieces are missing?
Number problems at primary level that require careful consideration.
In November, Liz was interviewed for an article on a parents' website about learning times tables. Read the article here.
This group activity will encourage you to share calculation strategies and to think about which strategy might be the most efficient.
Look at what happens when you take a number, square it and subtract your answer. What kind of number do you get? Can you prove it?
After training hard, these two children have improved their results. Can you work out the length or height of their first jumps?
Which is quicker, counting up to 30 in ones or counting up to 300 in tens? Why?
Can you find which shapes you need to put into the grid to make the
totals at the end of each row and the bottom of each column?
Number problems at primary level that may require determination.
This number has 903 digits. What is the sum of all 903 digits?
Start by putting one million (1 000 000) into the display of your
calculator. Can you reduce this to 7 using just the 7 key and add,
subtract, multiply, divide and equals as many times as you like?
Here is a picnic that Petros and Michael are going to share equally. Can you tell us what each of them will have?
Resources to support understanding of multiplication and division through playing with number.
A game for 2 people. Use your skills of addition, subtraction, multiplication and division to blast the asteroids.