Search by Topic

Resources tagged with Addition & subtraction similar to A Romantic Riddle:

Filter by: Content type:
Stage:
Challenge level: Challenge Level:1 Challenge Level:2 Challenge Level:3

There are 241 results

Broad Topics > Calculations and Numerical Methods > Addition & subtraction

problem icon

Dotty Six for Two

Stage: 1 and 2 Challenge Level: Challenge Level:1

Dotty Six game for an adult and child. Will you be the first to have three sixes in a straight line?

problem icon

Dotty Six

Stage: 1 and 2 Challenge Level: Challenge Level:1

Dotty Six is a simple dice game that you can adapt in many ways.

problem icon

Fingers and Hands

Stage: 2 Challenge Level: Challenge Level:1

How would you count the number of fingers in these pictures?

problem icon

Adding and Subtracting Positive and Negative Numbers

Stage: 2, 3 and 4

How can we help students make sense of addition and subtraction of negative numbers?

problem icon

Strike it Out

Stage: 1 and 2 Challenge Level: Challenge Level:1

Use your addition and subtraction skills, combined with some strategic thinking, to beat your partner at this game.

problem icon

Page Numbers

Stage: 2 Short Challenge Level: Challenge Level:1

Exactly 195 digits have been used to number the pages in a book. How many pages does the book have?

problem icon

Some Games That May Be Nice or Nasty

Stage: 2 and 3 Challenge Level: Challenge Level:1

There are nasty versions of this dice game but we'll start with the nice ones...

problem icon

Tug Harder!

Stage: 2 Challenge Level: Challenge Level:1

In this game, you can add, subtract, multiply or divide the numbers on the dice. Which will you do so that you get to the end of the number line first?

problem icon

Magic Squares 4x4

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

Fill in the numbers to make the sum of each row, column and diagonal equal to 34. For an extra challenge try the huge American Flag magic square.

problem icon

Six Is the Sum

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

What do the digits in the number fifteen add up to? How many other numbers have digits with the same total but no zeros?

problem icon

Sort Them Out (1)

Stage: 1 Challenge Level: Challenge Level:1

Can you each work out the number on your card? What do you notice? How could you sort the cards?

problem icon

How Many?

Stage: 1 Challenge Level: Challenge Level:1

This project challenges you to work out the number of cubes hidden under a cloth. What questions would you like to ask?

problem icon

Oddly

Stage: 2 Challenge Level: Challenge Level:3 Challenge Level:3 Challenge Level:3

Find the sum of all three-digit numbers each of whose digits is odd.

problem icon

Neighbours

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

In a square in which the houses are evenly spaced, numbers 3 and 10 are opposite each other. What is the smallest and what is the largest possible number of houses in the square?

problem icon

Pairs of Numbers

Stage: 1 Challenge Level: Challenge Level:1

If you have ten counters numbered 1 to 10, how many can you put into pairs that add to 10? Which ones do you have to leave out? Why?

problem icon

Two and Two

Stage: 2 and 3 Challenge Level: Challenge Level:3 Challenge Level:3 Challenge Level:3

How many solutions can you find to this sum? Each of the different letters stands for a different number.

problem icon

Become Maths Detectives

Stage: 2 Challenge Level: Challenge Level:1

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.

problem icon

Month Mania

Stage: 1 and 2 Challenge Level: Challenge Level:2 Challenge Level:2

Can you design a new shape for the twenty-eight squares and arrange the numbers in a logical way? What patterns do you notice?

problem icon

Cherries Come in Twos

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

Susie took cherries out of a bowl by following a certain pattern. How many cherries had there been in the bowl to start with if she was left with 14 single ones?

problem icon

Even and Odd

Stage: 1 Challenge Level: Challenge Level:1

This activity is best done with a whole class or in a large group. Can you match the cards? What happens when you add pairs of the numbers together?

problem icon

Four Goodness Sake

Stage: 2 Challenge Level: Challenge Level:3 Challenge Level:3 Challenge Level:3

Use 4 four times with simple operations so that you get the answer 12. Can you make 15, 16 and 17 too?

problem icon

Spell by Numbers

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

Can you substitute numbers for the letters in these sums?

problem icon

Mrs Beeswax

Stage: 1 Challenge Level: Challenge Level:2 Challenge Level:2

In how many ways could Mrs Beeswax put ten coins into her three puddings so that each pudding ended up with at least two coins?

problem icon

Brothers and Sisters

Stage: 2 Challenge Level: Challenge Level:1

Cassandra, David and Lachlan are brothers and sisters. They range in age between 1 year and 14 years. Can you figure out their exact ages from the clues?

problem icon

A Numbered Route

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

Can you draw a continuous line through 16 numbers on this grid so that the total of the numbers you pass through is as high as possible?

problem icon

Rod Measures

Stage: 2 Challenge Level: Challenge Level:3 Challenge Level:3 Challenge Level:3

Using 3 rods of integer lengths, none longer than 10 units and not using any rod more than once, you can measure all the lengths in whole units from 1 to 10 units. How many ways can you do this?

problem icon

One Wasn't Square

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

Mrs Morgan, the class's teacher, pinned numbers onto the backs of three children. Use the information to find out what the three numbers were.

problem icon

Napier's Bones

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

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?

problem icon

Reach 100

Stage: 2 Challenge Level: Challenge Level:3 Challenge Level:3 Challenge Level:3

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.

problem icon

One Million to Seven

Stage: 2 Challenge Level: Challenge Level:3 Challenge Level:3 Challenge Level:3

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?

problem icon

Magic Triangle

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

Place the digits 1 to 9 into the circles so that each side of the triangle adds to the same total.

problem icon

The Clockmaker's Birthday Cake

Stage: 2 Challenge Level: Challenge Level:1

The clockmaker's wife cut up his birthday cake to look like a clock face. Can you work out who received each piece?

problem icon

1, 2, 3 Magic Square

Stage: 2 Challenge Level: Challenge Level:1

Arrange three 1s, three 2s and three 3s in this square so that every row, column and diagonal adds to the same total.

problem icon

The Deca Tree

Stage: 2 Challenge Level: Challenge Level:1

Find out what a Deca Tree is and then work out how many leaves there will be after the woodcutter has cut off a trunk, a branch, a twig and a leaf.

problem icon

Diagonal Sums

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

In this 100 square, look at the green square which contains the numbers 2, 3, 12 and 13. What is the sum of the numbers that are diagonally opposite each other? What do you notice?

problem icon

Sometimes We Lose Things

Stage: 2 Challenge Level: Challenge Level:3 Challenge Level:3 Challenge Level:3

Well now, what would happen if we lost all the nines in our number system? Have a go at writing the numbers out in this way and have a look at the multiplications table.

problem icon

Reverse Trick

Stage: 2 Challenge Level: Challenge Level:1

Tell your friends that you have a strange calculator that turns numbers backwards. What secret number do you have to enter to make 141 414 turn around?

problem icon

Noah

Stage: 1 Challenge Level: Challenge Level:2 Challenge Level:2

Noah saw 12 legs walk by into the Ark. How many creatures did he see?

problem icon

Sam's Quick Sum

Stage: 2 Challenge Level: Challenge Level:3 Challenge Level:3 Challenge Level:3

What is the sum of all the three digit whole numbers?

problem icon

Number Juggle

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

Fill in the missing numbers so that adding each pair of corner numbers gives you the number between them (in the box).

problem icon

I'm Eight

Stage: 1, 2, 3 and 4 Challenge Level: Challenge Level:1

Find a great variety of ways of asking questions which make 8.

problem icon

Domino Square

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

Use the 'double-3 down' dominoes to make a square so that each side has eight dots.

problem icon

Sitting Round the Party Tables

Stage: 1 and 2 Challenge Level: Challenge Level:1

Sweets are given out to party-goers in a particular way. Investigate the total number of sweets received by people sitting in different positions.

problem icon

Some Secret Codes

Stage: 2 Challenge Level: Challenge Level:3 Challenge Level:3 Challenge Level:3

Can you follow the rule to decode the messages?

problem icon

Tug of War

Stage: 1 Challenge Level: Challenge Level:1

Can you use the numbers on the dice to reach your end of the number line before your partner beats you?

problem icon

Five Steps to 50

Stage: 1 Challenge Level: Challenge Level:1

Use five steps to count forwards or backwards in 1s or 10s to get to 50. What strategies did you use?

problem icon

Super Value Shapes

Stage: 2 Challenge Level: Challenge Level:1

If each of these three shapes has a value, can you find the totals of the combinations? Perhaps you can use the shapes to make the given totals?

problem icon

Birthday Cakes

Stage: 1 Challenge Level: Challenge Level:2 Challenge Level:2

Jack's mum bought some candles to use on his birthday cakes and when his sister was born, she used them on her cakes too. Can you use the information to find out when Kate was born?

problem icon

Sea Level

Stage: 2 Challenge Level: Challenge Level:1

The picture shows a lighthouse and many underwater creatures. If you know the markings on the lighthouse are 1m apart, can you work out the distances between some of the different creatures?

problem icon

Picture a Pyramid ...

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

Imagine a pyramid which is built in square layers of small cubes. If we number the cubes from the top, starting with 1, can you picture which cubes are directly below this first cube?