The difference is the result after subtracting one number from another.

When you adjust you make a change to a number. This is done to make a calculation easier to solve mentally.

Use equivalence and compensation strategies to solve subtraction problems in a range of contexts

Maths

Explain and represent constant difference for subtraction

Explain how constant difference can make written calculations more efficient

Use constant difference to balance equations and find unknowns

Explain how increasing or decreasing the minuend affects the difference

Solve subtraction calculations mentally by using known facts

Explain how adjusting the minuend can make mental calculation easier

Explain how adjusting the subtrahend affects the difference: reduction structure

Explain how adjusting the subtrahend affects the difference: partitioning

Calculate the difference using knowledge of an adjusted subtrahend: difference structure

In this unit pupils will explain how increasing or decreasing the minuend affects the difference and solve subtraction calculations mentally using known facts explaining how adjusting the minuend can make mental calculation easier In the future unit pupils will explain how to balance equations with addition or subtraction expressions and use their knowledge of balancing equations to solve problems

In the prior unit pupils used the concept of same sum to simplify and solve addition problems  In this unit pupils will explain how increasing or decreasing the minuend affects the difference and solve subtraction calculations mentally by using known facts explaining how adjusting the minuend can make mental calculation easier

In this unit pupils will explain how increasing or decreasing the minuend affects the difference and solve subtraction calculations mentally by using known facts explaining how adjusting the minuend can make mental calculation easier.

Use equivalence and compensation to simplify and solve subtraction problems

Sticky sticks have a goal difference of 17 before they play two matches. They win both their matches 2:0 and 3:0  What is their goal difference now?

Polar Bears have a goal difference of 12 before they play two matches. They win the first match 4:2 but lose the second 1:5. What is their goal difference now?

Happy Feet have a goal difference of 19 before they play three more fixtures. They win 2:1, lose 1:4 and lose 0:3 in the matches. What is their goal difference now?

Bolly Bears have a goal difference of 16 before they play three more fixtures. They draw 2:2, win 5:2 and lose 0:2 in the matches. What is their goal difference now?

Bolly Bears have a goal difference of 17 and Polar Bears a goal difference of 12  They play one another and Polar Bears win 5:3. Who has the greatest goal difference now?

Happy Feet, Skatey Spuds and Lucky Pucky all have a goal difference of 14   They each play one another with the results shown here. Which of these shows the goal difference from greatest to smallest?

In the bar model shown, which team has scored the most goals?

Select the phrase to complete the definition of constant difference. If the minuend and subtrahend are adjusted by the same amount, the difference ...

Which pair of expressions have the same difference?

Solve the following calculation mentally by adjusting the minuend and then the difference.
10,007 − 244 = {{ }}

Solve the following calculation by adjusting both subtrahend and minuend to create an easier subtraction.
{{ }} = 752 − 347

Look at the pair of equations below and use the complete one to help find the missing number in the second.

Starter Quiz

In the bar model shown, which team has scored the most goals?