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Operations on natural numbers

Justifying the steps

Types of exercises: justifying the steps - properties of operations.

Exercises are drawn at random from a large bank - every click gives a different set.

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All The four operations Written methods Squares and cubes Higher powers Order of operations Estimating Division with remainder Prime factorisation Divisibility, GCD and LCM How many numbers have a given property Justifying the steps

Solved: 0 of 10

Problem

Philip calculated cleverly and wrote: 26 + 24 + 74 = 26 + 74 + 24. Which property of operations was used in this step?

Problem

Philip calculated cleverly and wrote: 2 · 34 · 5 = 2 · 5 · 34. Which property of operations was used in this step?

Problem

Adam calculated cleverly and wrote: (120 + 15) : 3 = 120 : 3 + 15 : 3. Which property of operations was used in this step?

Problem

Michael calculated cleverly and wrote: 7 · 102 = 7 · 100 + 7 · 2. Which property of operations was used in this step?

Problem

Sophie calculated cleverly and wrote: (180 + 12) : 6 = 180 : 6 + 12 : 6. Which property of operations was used in this step?

Problem

Sophie calculated cleverly and wrote: 2 · 20 · 50 = 2 · 50 · 20. Which property of operations was used in this step?

Problem

Sophie calculated cleverly and wrote: 4 · 105 = 4 · 100 + 4 · 5. Which property of operations was used in this step?

Problem

Ola calculated cleverly and wrote: 3 · 103 = 3 · 100 + 3 · 3. Which property of operations was used in this step?

Problem

John calculated cleverly and wrote: 2 · 21 · 50 = 2 · 50 · 21. Which property of operations was used in this step?

Problem

Michael calculated cleverly and wrote: (36 · 5) · 2 = 36 · (5 · 2). Which property of operations was used in this step?

This address is one particular set - everyone who opens it gets exactly the same exercises. Copy the link from the address bar and send it to the class. You can generate a new set at the top of the page.

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