# NRICH PROBLEM SOLVING NUMBER BONDS

Odd Squares Age 7 to 11 Challenge Level: How many hens were there? Number Balance Age 5 to 7 Challenge Level: You may also like Cubes How many faces can you see when you arrange these three cubes in different ways? What happens when you add pairs of the numbers together? Each grab some coins, return some, then share equally what they had put back, finishing with their own share. Generalising from a number of examples and stating a rule Maths is shot through with patterns.

Abundant Numbers Age 7 to 11 Challenge Level: How much is the chocolate bar? This problem challenges you to find out how many odd numbers there are between pairs of numbers. Two Spinners Age 5 to 7 Challenge Level: A game for 1 person to play on screen. If your children know and use the convention of the order of operations this can be an opportunity to ask whether the order that they have written the calculations in is the same as the order in which they would do them. Or did they have a more systematic approach to the problem?

What did you do next? Using the interactive, place a few triangles in the big triangle, making sure that touching faces add to 10 and ask children to think about what they notice.

Always, Sometimes or Never?

Can you find 2 butterflies to go on each flower so that the numbers on each pair of butterflies adds to the same number as the one on the flower?

In Sticky Triangles KS2 pupils are asked to make geometric patterns with problemm and predict how many they would need to continue the pattern. A game for 2 or more players with a pack of cards. Age 7 to 11 Challenge Level: Which sorts of calculations make the most difference to the total?

A game to be played against the computer, or in groups. What Was in the Box? Slide the shared counter across several nich numbers, adding them up as you go to make a ‘running’ total. Largest Even Age 5 to 7 Challenge Level: If not, why don’t you?

Which numbers of bears can they share so that there are none left over? Do you get the same answer every time from your string of calculations?

## Sealed Solution

An investigation looking at doing and undoing mathematical operations focusing on doubling, halving, adding and subtracting.

Doing and Undoing Age 5 to 11 Challenge Level: Totality for Two Age 5 to 11 Challenge Level: One Big Triangle Here are nine triangles. How close can you get to with just adding? What questions would you like to ask? Four Go Age 7 to 11 Challenge Level: Noah saw 12 legs walk by into the Ark. Strike it Out Age 5 to 11 Challenge Level: Two Spinners Age 5 to 7 Challenge Level: Age 5 to 7 Challenge Level: Andrew decorated 20 biscuits to take to a party.

PROBLEM SOLVING WORKSHOP MIXED PROBLEM SOLVING 3.1-3.4 ANSWERS

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# Pairs of Numbers :

Using the Dotty Six Activity as a Springboard for Investigation Age 5 to 11 This article suggests how to dig deeper into who answers questions in your classroom using the game Dotty Six.

Probllem do you notice? Can you pdoblem 2 butterflies to go on each flower so that the numbers on each pair of butterflies adds to the same number as the one on the flower?

As they explain their working, record it in order on the board, for example:.

# Making Algebra Rich :

Practise your skills of addition, subtraction, multiplication and division to hit the target score. Throw the dice and decide whether to double or halve the number. Exploring the structure of a number square: