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 how constant difference can make written calculations more efficient

Maths

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

Use equivalence and compensation to simplify and solve subtraction problems

Which of the following expressions is not equivalent to the others?

Match the expression with the adjustment to the minuend and subtrahend that will make them more efficient for calculation.

Use adjustment of the minuend and subtrahend followed by your understanding of place value.
20.58 − 5.96 = {{ }}

Use adjustment of the minuend and subtrahend followed by partitioning to calculate the following subtraction.
70,559 − 54,504 = {{ }}

Use adjustment followed by a written procedure to calculate the following.
40,000 − 2,654 = {{ }}

Match the pairs of number complements to 100

Use a mental strategy to sum these multiples of 10
560 + 120 = {{ }}

Add together these multiples of 1,000 using a mental strategy.
{{ ]} = 15,000 + 27,000

Complete this subtraction using a mental strategy.
67,000 − 12,000 = {{ }}

How much change would I get from £20 if I spent £11.75 on a new football? £{{ }} change.

I have a ball of old plasticine that weighs 750 g and a new jumbo pack that weight 1.2 kg. What mass of plasticine do I have altogether?

This lesson will soon be taken down.

Explain how constant difference can make written calculations more efficient

Lesson outcome