There are **430** NRICH Mathematical resources connected to **Working systematically**, you may find related items under Thinking Mathematically.

Challenge Level

Can you find all the ways to get 15 at the top of this triangle of numbers? Many opportunities to work in different ways.

Challenge Level

Use the numbers and symbols to make this number sentence correct. How many different ways can you find?

Challenge Level

This challenge is about finding the difference between numbers which have the same tens digit.

Challenge Level

In this calculation, the box represents a missing digit. What could the digit be? What would the solution be in each case?

Challenge Level

Have a go at balancing this equation. Can you find different ways of doing it?

Challenge Level

Use two dice to generate two numbers with one decimal place. What happens when you round these numbers to the nearest whole number?

Challenge Level

What happens when you round these numbers to the nearest whole number?

Challenge Level

Can you work out some different ways to balance this equation?

Challenge Level

Can you complete this calculation by filling in the missing numbers? In how many different ways can you do it?

Challenge Level

What two-digit numbers can you make with these two dice? What can't you make?

Challenge Level

My local DIY shop calculates the price of its windows according to the area of glass and the length of frame used. Can you work out how they arrived at these prices?

Challenge Level

In this game for two players, you throw two dice and find the product. How many shapes can you draw on the grid which have that area or perimeter?

Challenge Level

Try this matching game which will help you recognise different ways of saying the same time interval.

Challenge Level

What is the largest 'ribbon square' you can make? And the smallest? How many different squares can you make altogether?

Challenge Level

How many possible necklaces can you find? And how do you know you've found them all?

Challenge Level

How could you arrange at least two dice in a stack so that the total of the visible spots is 18?

Challenge Level

Investigate the different numbers of people and rats there could have been if you know how many legs there are altogether!

Challenge Level

What happens when you add three numbers together? Will your answer be odd or even? How do you know?

Challenge Level

Can you see who the gold medal winner is? What about the silver medal winner and the bronze medal winner?

Challenge Level

Can you use the information to find out which cards I have used?

Challenge Level

In this problem it is not the squares that jump, you do the jumping! The idea is to go round the track in as few jumps as possible.

Challenge Level

What could the half time scores have been in these Olympic hockey matches?

Challenge Level

How could you put these three beads into bags? How many different ways can you do it? How could you record what you've done?

Challenge Level

How many ways can you find to do up all four buttons on my coat? How about if I had five buttons? Six ...?

Challenge Level

My dice has inky marks on each face. Can you find the route it has taken? What does each face look like?

Challenge Level

Tom and Ben visited Numberland. Use the maps to work out the number of points each of their routes scores.

Challenge Level

Two children made up a game as they walked along the garden paths. Can you find out their scores? Can you find some paths of your own?

Challenge Level

What can you say about these shapes? This problem challenges you to create shapes with different areas and perimeters.

Challenge Level

This cube has ink on each face which leaves marks on paper as it is rolled. Can you work out what is on each face and the route it has taken?

Challenge Level

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

Challenge Level

My coat has three buttons. How many ways can you find to do up all the buttons?

Challenge Level

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?

Challenge Level

This task depends on groups working collaboratively, discussing and reasoning to agree a final product.

Challenge Level

This 100 square jigsaw is written in code. It starts with 1 and ends with 100. Can you build it up?

Challenge Level

Can you put the numbers 1-5 in the V shape so that both 'arms' have the same total?

Challenge Level

If you are given the mean, median and mode of five positive whole numbers, can you find the numbers?

Challenge Level

Place the numbers 1 to 6 in the circles so that each number is the difference between the two numbers just below it.

Challenge Level

A group of children are using measuring cylinders but they lose the labels. Can you help relabel them?

Challenge Level

Different combinations of the weights available allow you to make different totals. Which totals can you make?

Challenge Level

Use your logical-thinking skills to deduce how much Dan's crisps and ice-cream cost altogether.

Challenge Level

Do you notice anything about the solutions when you add and/or subtract consecutive negative numbers?

Challenge Level

Add or subtract the two numbers on the spinners and try to complete a row of three. Are there some numbers that are good to aim for?

Challenge Level

Use the differences to find the solution to this Sudoku.

Challenge Level

These eleven shapes each stand for a different number. Can you use the number sentences to work out what they are?

Challenge Level

How many different triangles can you draw on the dotty grid which each have one dot in the middle?

Challenge Level

Find the product of the numbers on the routes from A to B. Which route has the smallest product? Which the largest?

Challenge Level

This Sudoku puzzle can be solved with the help of small clue-numbers on the border lines between pairs of neighbouring squares of the grid.

Challenge Level

Ben and his mum are planting garlic. Can you find out how many cloves of garlic they might have had?

Challenge Level

The puzzle can be solved with the help of small clue-numbers which are either placed on the border lines between selected pairs of neighbouring squares of the grid or placed after slash marks on. . . .