Starter quiz
- Select the prime numbers.
- 3 ✓
- 7 ✓
- 9
- 11 ✓
- 15
-
- Look at the long multiplication below, what is the missing partial product?
- '28,152' ✓
- Select the numbers that are factors of 12
- 1 ✓
- 3 ✓
- 5
- 8
- 60
-
- Which of these is the complete list for the factors of 16?
- 2, 8
- 1, 2, 8, 16
- 1, 2, 4, 8, 16 ✓
-
- What is the missing factor of 72? 1, 2, 3, 4, 6, 8, 9, 12, ______, 24, 36, 72
- '18' ✓
- Sam and Andeep are estimating the total number of visitors across the 35 Olympic venues on one day. Each venue has on average 6,012 visitors per day. How many visitors on average, visited on this day?
- '210,420' ✓
Exit quiz
- Look at the numbers below and select the prime numbers.
- 23 ✓
- 24
- 27
- 28
- 29 ✓
-
- Select the composite numbers.
- 23
- 25 ✓
- 41
- 42 ✓
- 55 ✓
-
- Which of these are ways that 14 could be represented with its factors?
- 2 and 7 ✓
- 1 and 14 ✓
- 7 and 7
- 3 and 11
-
- Select the expressions that are equivalent to 23 × 3 × 9
- 3 × 23 × 9 ✓
- 9 × 3 × 23 ✓
- 6 × 3 × 23
- 23 × 27
-
- Select the expressions that are equivalent to 24 × 18
- 24 × 1 × 17
- 24 × 2 × 9 ✓
- 24 × 3 × 6 ✓
- 24 × 3 × 15
-
- Look at the equation. Find the missing number. 29 × 33 = 29 × 3 × ______.
- '11' ✓
Worksheet
Loading worksheet ...
Presentation
Loading presentation ...
Lesson Details
Key learning points
- Multiplication can be simplified by factorising one of the factors.
- Look at the factors to identify which are composite numbers.
- Composite numbers can be factorised.
- Multiplication is commutative.
- Factors can be grouped in different ways and the product remains the same.
Common misconception
Pupils can identify factors of a 2-digit number but do not consider efficiency when multiplying.
Draw attention to factor pairs and those which result in easier calculations e.g. pupils often find multiplying by 4 or 5 easier than 7, or can apply doubling when multiplying by 2
Keywords
Associative law - The associative law states that it doesn't matter how you group or pair values (i.e. which we calculate first), the result is still the same. It applies for addition and multiplication.
Composite number - A composite number is an integer with more than two factors. All integers greater than 1 are either composite or prime.
+