Number Operations & Calculation Methods
Consecutive Numbers
An investigation involving adding and subtracting sets of consecutive numbers. Lots to find out, lots to explore.
Can You Make 100?
How many ways can you find to put in operation signs (+, −, ×, ÷) to make 100?
Where Can We Visit?
Charlie and Abi put a counter on 42. They wondered if they could visit all the other numbers on their 1-100 board, moving the counter using just these two operations: x2 and -5. What do you think?
Two and Two
How many solutions can you find to this sum? Each of the different letters stands for a different number.
Number Daisy
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?
Remainders
I'm thinking of a number. My number is both a multiple of 5 and a multiple of 6. What could my number be?
Largest Product
Which set of numbers that add to 100 have the largest product?
Cinema Problem
A cinema has 100 seats. Show how it is possible to sell exactly 100 tickets and take exactly £100 if the prices are £10 for adults, 50p for pensioners and 10p for children.
Consecutive Seven
Can you arrange these numbers into 7 subsets, each of three numbers, so that when the numbers in each are added together, they make seven consecutive numbers?
Method in Multiplying Madness?
Watch our videos of multiplication methods that you may not have met before. Can you make sense of them?
The Remainders Game
Play this game and see if you can figure out the computer's chosen number.
Countdown
Here is a chance to play a version of the classic Countdown Game.
Going Round in Circles
Mathematicians are always looking for efficient methods for solving problems. How efficient can you be?
Missing Multipliers
What is the smallest number of answers you need to reveal in order to work out the missing headers?
Impossibilities
Just because a problem is impossible doesn't mean it's difficult...
Overlaps
Can you find ways to put numbers in the overlaps so the rings have equal totals?
Have You Got It?
Can you explain the strategy for winning this game with any target?
Egyptian Fractions
The Egyptians expressed all fractions as the sum of different unit fractions. Here is a chance to explore how they could have written different fractions.
Fractions Jigsaw
A jigsaw where pieces only go together if the fractions are equivalent.
Round and Round and Round
Where will the point stop after it has turned through 30 000 degrees? I took out my calculator and typed 30 000 ÷ 360. How did this help?
Twisting and Turning
Take a look at the video and try to find a sequence of moves that will untangle the ropes.
More Twisting and Turning
It would be nice to have a strategy for disentangling any tangled ropes...
Connect Three
In this game the winner is the first to complete a row of three. Are some squares easier to land on than others?
Consecutive Negative Numbers
Do you notice anything about the solutions when you add and/or subtract consecutive negative numbers?
Adding and Subtracting Positive and Negative Numbers
How can we help students make sense of addition and subtraction of negative numbers?
Weights
Different combinations of the weights available allow you to make different totals. Which totals can you make?
Keep it Simple
Can all unit fractions be written as the sum of two unit fractions?
The Greedy Algorithm
The Egyptians expressed all fractions as the sum of different unit fractions. The Greedy Algorithm might provide us with an efficient way of doing this.
Countdown Fractions
Here is a chance to play a fractions version of the classic Countdown Game.
Magic Letters
Charlie has made a Magic V. Can you use his example to make some more? And how about Magic Ls, Ns and Ws?
Strange Bank Account
Imagine a very strange bank account where you are only allowed to do two things...
Up, Down, Flying Around
Play this game to learn about adding and subtracting positive and negative numbers
Same Answer
Aisha's division and subtraction calculations both gave the same answer! Can you find some more examples?
Almost One
Choose some fractions and add them together. Can you get close to 1?
5 by 5 Mathdokus
Can you use the clues to complete these 5 by 5 Mathematical Sudokus?