The minuend is the number being subtracted from.

A subtrahend is a number subtracted from another.

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

A constant is a quantity that has a fixed value that does not change or vary, such as a number.

Explain and represent constant difference for subtraction

Maths

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

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

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

What is the constant difference between all of the expressions below?
99 − 27 = 89 − 17 = 79 − 7

Which word fills in the blank in this sentence?
If the minuend and subtrahend are changed by the same amount, the difference remains __________.

What is the constant difference being shown in these expressions? 28 − 12     40 − 24     115 − 99

What is the missing number in the equation below?
16 − 9 = 36 − {{ }}

Sam has 34 more flying robots than aqua robots. Sam gives away 12 flying robots and 12 aqua robots.
How many more more flying robots than aqua robots does Sam have now?

Jacob and Sam have a go at archery. Jacob scores 18 points and Sam scores 35 points. They have a second go and both score 25 more. By how many points has Sam won? {{ }} points

Match the pairs of number complements to 100

Use a mental strategy to sum these multiples of 10
340 + 500 = {{ }}

Add together these multiples of 1,000 using a mental strategy.
{{ }} = 12,000 + 7,000

Complete this subtraction using a mental strategy.
19,000 − 15,000 = {{ }}

How much change would I get from £20 if I spent £13.50 on a new football? £{{ }} change.

I have a ball of old plasticine that weighs 400 g and a new jumbo pack that weighs 1 kg. What mass of plasticine do I have altogether?

Explain and represent constant difference for subtraction

Lesson outcome