# NRICH PROBLEM SOLVING PLACE VALUE

Can you get close to than your partner? Trebling Age 7 to 11 Challenge Level: Subtraction Surprise Age 7 to 14 Challenge Level: Who had made the highest even number? Evaluate these powers of You could start by thinking about how each of them would write our number 7. What happens when you add a three digit number to its reverse? Napier’s Bones Age 7 to 11 Challenge Level: Number problems for inquiring primary learners. It is also noticeable that there are five empty boxes remaining, in a similar shape to the full boxes. Can you work out some different ways to balance this equation? In this twist on the well-known Countdown numbers game, use your knowledge of Powers and Roots to make a target.

Investigate the different ways these aliens count in this challenge. Number problems at primary level that require careful consideration.

The Scot, John Napier, invented these strips about years ago to help calculate multiplication and division. Age 7 to 11 Challenge Level: This is vzlue to say that young children will not also have an awareness of much larger numbers.

Sixty-seven Squared Age 16 to 18 Challenge Level: Age 11 to 14 Challenge Level: What do you notice about the numbers that it produces? What can you say about each number’s relationship to ten? Use your knowledge of place value to beat your opponent.

TOK ESSAY PPD FORM Number problems for inquiring primary learners. This article suggests some ways of making sense of calculations involving positive and negative numbers.

## Place Value, Integers, Ordering & Rounding

Sweets are given out to party-goers in a particular way. What happens when you round these numbers to the nearest whole number? Can you build it up? How many different ways can you do this? What happens when you round these numbers to the nearest whole number?

Big Powers Age 11 to 16 Challenge Level: Two-digit Targets Age 5 to 7 Challenge Level: Can you sort out the clues and find the number? Once a basic number sense has developed for numbers up to ten, a strong ‘sense of ten’ needs to be developed as a foundation for both place value and mental calculations.

Place the numbers from 1 to 9 in the squares below so that the difference between joined squares is odd.

Can you reduce this to 7 using just the 7 key and add, subtract, multiply, divide and equals as many times as you like? Can you complete this calculation by filling in the missing numbers?

XKCD COMPUTER PROBLEM SOLVING FLOWCHART

# Place Value: the Ten-ness of Ten :

This activity focuses on rounding to the nearest Three people chose this problwm a favourite problem. Adding with the Abacus Age 5 to 16 Nowadays the calculator is very familiar to many of us. What numbers are illustrated? How would you create the largest possible two-digit even number from the digit I’ve given you and one of your choice? Can you find the chosen number from the grid using the clues?

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Method in Multiplying Madness? To support valeu aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

What two-digit numbers can you make with these two dice? How many solutions can you find to this sum? Who said that adding, subtracting, multiplying and dividing couldn’t be fun? Trebling Age 7 to 11 Challenge Level: 