5.3.2

Addition & Subtraction

Test yourself on Addition & Subtraction

Test your knowledge with free interactive questions on Seneca — used by over 10 million students.

Addition in your Head

You can use knowledge of place value and number bonds to help us add.

67 + 91

67 + 91

  • When trying to work out 67 + 91, you need to use your number bonds.
    • You know that 7 + 1 = 8.
    • So your 'ones' must be 8.
'Tens'

'Tens'

  • You know that 9 + 6 = 15.
    • So your 'tens' must be 15.
    • 15 'tens' is the same as 5 'tens' and 1 'hundred'.
And the answer is...

And the answer is...

  • So there are:
    • 8 'ones'.
    • 5 'tens'.
    • 1 'hundred'.
  • The answer is to 67 + 91 is 158.
98 + 15

98 + 15

  • This is the same even if there is carrying to do!
    • You know that 8 + 5 = 13.
    • So your 'ones' must be 13.
    • You will need to carry the 1 into the 'tens' column.
The 'tens'

The 'tens'

  • You know that 9 + 1 = 10.
  • You need to add 1 more from the 1 you carried from the 'ones'.
    • So your 'tens' must be 11.
    • 11 'tens' is the same as 1 'ten' and 1 'hundred'.
And the answer is...

And the answer is...

  • So there are:
    • 3 'ones'.
    • 1 'ten'.
    • 1 'hundred'.
  • The answer is to 98 + 15 is 113.

Subtraction in your Head

You can use knowledge of place value and number bonds to help us subtract.

67 − 23

67 − 23

  • When trying to work out 67 − 23, you need to use your number bonds.
    • You know that 7 − 3 = 4.
    • So your 'ones' must be 4.
'Tens'

'Tens'

  • You know that 6 − 2 = 4.
    • So your 'tens' must be 4.
And the answer is...

And the answer is...

  • So there are:
    • 4 'ones'.
    • 4 'tens'.
  • The answer is to 67 − 23 is 44.
73 − 18

73 − 18

  • This is the same even if there is borrowing (exchanging) to do!
  • You can use number bonds to help you when you need to borrow (exchange) in a subtraction.
    • You know that 3 + 5 + 10 = 18.
    • So 73 − 3 − 5 − 10 = 73 − 18.
And the answer is...

And the answer is...

  • 73 − 3 − 5 − 10 = 55.
Jump to other topics
1

Year 5 - Number

2

Year 5 - Measurement

3

Year 5 - Geometry

4

Year 5 - Statistics

5

Year 6 - Number

6

Year 6 - Ratio & Proportion

7

Year 6 - Algebra

8

Year 6 - Measurement

9

Year 6 - Statistics

9.1

Displaying Data

9.2

Averages

Practice questions on Addition & Subtraction

Can you answer these? Test yourself with free interactive practice on Seneca — used by over 10 million students.

  1. 1
  2. 2
  3. 3
    What is 56 + 83?Multiple choice
  4. 4
    What is 21 + 93?Multiple choice
  5. 5
    What is 48 + 37?Multiple choice
Answer all questions on Addition & Subtraction

Unlock your full potential with Seneca Premium

  • Unlimited access to 10,000+ open-ended exam questions

  • Mini-mock exams based on your study history

  • Unlock 800+ premium courses & e-books

Get started with Seneca Premium