Subtract from a 2-digit number using column subtraction with regrouping | Maths

Starter quiz

Which number in the column subtraction is the minuend?

41

44

85 ✓
Which number in the column subtraction is the subtrahend?

41 ✓

44

85
Calculate the missing difference using the column subtraction.

14

24 ✓

26

86
Calculate the missing difference using the column subtraction.

'134' ✓
What is the missing tens digit?

'2' ✓
What is the missing subtrahend?

'232' ✓

Exit quiz

A ten has been regrouped into 10 ones. What number is represented by the base ten blocks?

'44' ✓
In which of these calculations would you need to regroup?
Calculate the difference.

37

45

47 ✓

63
What is the missing subtrahend?

'8' ✓
Calculate the difference.

28 ✓

32

38

96
What is the missing subtrahend?

'16' ✓

Worksheet

Loading worksheet ...

Presentation

Loading presentation ...

Video

Lesson Details

Key learning points

Start with the numbers with the smallest place value.
Regroup when the ones digit of the subtrahend is greater than the ones digit of the minuend.
Change the number of ones and tens in the minuend.

Common misconception

Pupils may not understand column subtraction. They may use regrouping without grasping the reasoning behind the algorithm.

Ensure that pupils understand the purpose of regrouping and the value of the numbers when they are using column subtraction. Spend more time using base ten blocks with regrouping if pupils are not ready to progress onto the formal algorithm.

Keywords

Column subtraction - Column subtraction is a way of subtracting numbers by writing a number below another.
Regroup - The process of unitising and exchanging between place values is known as regrouping.