In this investigation, you are challenged to make mobile phone
numbers which are easy to remember. What happens if you make a
sequence adding 2 each time?
EWWNP means Exploring Wild and Wonderful Number Patterns Created by Yourself! Investigate what happens if we create number patterns using some simple rules.
If the numbers 5, 7 and 4 go into this function machine, what
numbers will come out?
Find another number that is one short of a square number and when
you double it and add 1, the result is also a square number.
Find the next number in this pattern: 3, 7, 19, 55 ...
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?
Use this grid to shade the numbers in the way described. Which
numbers do you have left? Do you know what they are called?
On Friday the magic plant was only 2 centimetres tall. Every day it
doubled its height. How tall was it on Monday?
Can you work out how many flowers there will be on the Amazing Splitting Plant after it has been growing for six weeks?
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?
If the answer's 2010, what could the question be?
Ben’s class were making cutting up number tracks. First they
cut them into twos and added up the numbers on each piece. What
patterns could they see?
These sixteen children are standing in four lines of four, one
behind the other. They are each holding a card with a number on it.
Can you work out the missing numbers?
What happens when you add the digits of a number then multiply the
result by 2 and you keep doing this? You could try for different
numbers and different rules.
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?
We can arrange dots in a similar way to the 5 on a dice and they
usually sit quite well into a rectangular shape. How many
altogether in this 3 by 5? What happens for other sizes?
This problem is based on the story of the Pied Piper of Hamelin. Investigate the different numbers of people and rats there could have been if you know how many legs there are altogether!
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?
Look at different ways of dividing things. What do they mean? How might you show them in a picture, with things, with numbers and symbols?
This article for teachers looks at how teachers can use problems from the NRICH site to help them teach division.
What is the lowest number which always leaves a remainder of 1 when
divided by each of the numbers from 2 to 10?
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?
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?
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. . . .
Put operations signs between the numbers 3 4 5 6 to make the highest possible number and lowest possible number.
Can you arrange 5 different digits (from 0 - 9) in the cross in the
Grandma found her pie balanced on the scale with two weights and a
quarter of a pie. So how heavy was each pie?
On my calculator I divided one whole number by another whole number and got the answer 3.125 If the numbers are both under 50, what are they?
Find at least one way to put in some operation signs (+ - x ÷)
to make these digits come to 100.
Use this information to work out whether the front or back wheel of
this bicycle gets more wear and tear.
Resources to support understanding of multiplication and division through playing with number.
Use your logical-thinking skills to deduce how much Dan's crisps
and ice-cream cost altogether.
Explore Alex's number plumber. What questions would you like to ask? What do you think is happening to the numbers?
In November, Liz was interviewed for an article on a parents' website about learning times tables. Read the article here.
What is happening at each box in these machines?
A game for 2 people. Use your skills of addition, subtraction, multiplication and division to blast the asteroids.
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?
This number has 903 digits. What is the sum of all 903 digits?
Use your logical reasoning to work out how many cows and how many
sheep there are in each field.
Can you design a new shape for the twenty-eight squares and arrange
the numbers in a logical way? What patterns do you notice?
What do you notice about the date 03.06.09? Or 08.01.09? This
challenge invites you to investigate some interesting dates
This group activity will encourage you to share calculation
strategies and to think about which strategy might be the most
How would you count the number of fingers in these pictures?
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?
At the beginning of May Tom put his tomato plant outside. On the
same day he sowed a bean in another pot. When will the two be the
Using the statements, can you work out how many of each type of
rabbit there are in these pens?
Twizzle, a female giraffe, needs transporting to another zoo. Which
route will give the fastest journey?
Here is a picnic that Chris and Michael are going to share equally.
Can you tell us what each of them will have?
Explore Alex's number plumber. What questions would you like to
ask? Don't forget to keep visiting NRICH projects site for the
latest developments and questions.