Addition and Subtraction
Strike it Out
Use your addition and subtraction skills, combined with some strategic thinking, to beat your partner at this game.
Fifteen Cards
Can you use the information to find out which cards I have used?
Consecutive Numbers
An investigation involving adding and subtracting sets of consecutive numbers. Lots to find out, lots to explore.
Play to 37
In this game for two players, the idea is to take it in turns to choose 1, 3, 5 or 7. The winner is the first to make the total 37.
Build it Up
Can you find all the ways to get 15 at the top of this triangle of numbers? Many opportunities to work in different ways.
Buying a Balloon
Lolla bought a balloon at the circus. She gave the clown six coins to pay for it. What could Lolla have paid for the balloon?
Subtraction Surprise
Try out some calculations. Are you surprised by the results?
Super Shapes
The value of the circle changes in each of the following problems. Can you discover its value in each problem?
Space Distances
This task focuses on distances travelled by the asteroid Florence. It's an opportunity to work with very large numbers.
Make 37
Four bags contain a large number of 1s, 3s, 5s and 7s. Can you pick any ten numbers from the bags so that their total is 37?
Finding Fifteen
Tim had nine cards each with a different number from 1 to 9 on it. How could he have put them into three piles so that the total in each pile was 15?
Roll These Dice
Roll two red dice and a green dice. Add the two numbers on the red dice and take away the number on the green. What are all the different possible answers?
Maze 100
Can you go through this maze so that the numbers you pass add to exactly 100?
Domino Square
Use the 'double-3 down' dominoes to make a square so that each side has eight dots.
Six Ten Total
This challenge combines addition, multiplication, perseverance and even proof.
Six Numbered Cubes
This task combines spatial awareness with addition and multiplication.
Amy's Dominoes
Amy has a box containing domino pieces but she does not think it is a complete set. Which of her domino pieces are missing?
What Distance?
Can you use addition and subtraction to answer these questions about real-life distances?
Twenty Divided Into Six
Katie had a pack of 20 cards numbered from 1 to 20. She arranged the cards into 6 unequal piles where each pile added to the same total. What was the total and how could this be done?
Reach 100
Choose four different digits from 1-9 and put one in each box so that the resulting four two-digit numbers add to a total of 100.
Sealed Solution
Ten cards are put into five envelopes so that there are two cards in each envelope. The sum of the numbers inside it is written on each envelope. What numbers could be inside the envelopes?
Got It
A game for two people, or play online. Given a target number, say 23, and a range of numbers to choose from, say 1-4, players take it in turns to add to the running total to hit their target.
Dice in a Corner
How could you arrange at least two dice in a stack so that the total of the visible spots is 18?
4 Dom
Use these four dominoes to make a square that has the same number of dots on each side.