1.3.4

Missing Number Problems

Test yourself on Missing Number Problems

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

Missing Number Problems

We can use our knowledge of number relationships, number facts and inverse operations to find the missing number in a calculation.

Missing number

Missing number

  • Sometimes we have to work out the missing number in a multiplication or division equation.
  • This is not always the number after the = sign.
  • For example:
    • ? x 5 = 15
    • 4 ÷ ? = 2
Number facts

Number facts

  • We can use our knowledge to help find the missing number.
    • ? x 5 = 15
  • We know from our 5 times table that:
    • 3 x 5 is 15
  • The missing number is 3.
Bar models

Bar models

  • We can use bar models to find the missing number.
    • 24 ÷ ? = 4
  • We can see there are 6 squares. Each square is equal to 4.
  • The missing number is 6.
Inverse operations

Inverse operations

  • We can use inverse operations to find the missing number.
    • ? x 5 = 15
  • The inverse is 15 ÷ 5 = 3.
  • The missing number is 3.
Jump to other topics
1

Year 3 - Number

2

Year 3 - Measurement

3

Year 3 - Geometry

4

Year 3 - Statistics

5

Year 4 - Number

6

Year 4 - Measurement

7

Year 4 - Geometry

8

Year 4 - Statistics

Practice questions on Missing Number Problems

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

  1. 1
  2. 2
  3. 3
Answer all questions on Missing Number Problems

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