Types of Numbers www mathsrevision com Level 2

Types of Numbers www. mathsrevision. com Level 2 Multiples and LCM Factors and HCF Prime numbers Prime Decomposition 19 -Oct-21 Created by Mr. Lafferty

Time Left : 0 8 mins 7 6 5 4 3 12 Starter Questions Level 2 www. mathsrevision. com 31 o 100 92 o o 45 19 -Oct-21 Created by Mr. Lafferty o

Types of Numbers Multiples www. mathsrevision. com Level 2 Learning Intention Success Criteria 1. We are learning that multiples are simply values in the times tables 1. Remember times tables and use them for multiples. 2. We are learning how to find the Lowest Common Multiple. 2. Apply sets of multiples to identify Lowest Common Multiples 19 -Oct-21 Created by Mr. Lafferty

Types of Numbers Multiples www. mathsrevision. com Level 2 Example 1 : Find the first seven multiples of 3. M 3 = 3, 6 , 9, 12, 15, 18, 21 Example 2 : Find the first five multiples of 4. M 4 = 4, 8 , 12, 16, 20, ……… 19 -Oct-21 Created by Mr. Lafferty

Types of Numbers Lowest Common Multiple www. mathsrevision. com Level 2 Lowest Common Multiple Smallest Same Number We need to write out multiples in order to find the Lowest Common Multiple. 19 -Oct-21 Created by Mr. Lafferty

Types of Numbers Lowest Common Multiple www. mathsrevision. com Level 2 Example : Find the LCM of 3 and 4. M 3 = 3, 6 , 9, 12, 15, ……… M 4 = 4, 8 , 12, 16, 20, ……… LCM = 12 19 -Oct-21 Created by Mr. Lafferty

Types of Numbers www. mathsrevision. com Level 2 Now try Exercise 1 Ch 5 (page 28) 19 -Oct-21 Created by Mr. Lafferty

Starter Questions www. mathsrevision. com Level 2 65 o 150 52 o 19 -Oct-21 Created by Mr. Lafferty o

Types of Numbers Using Factors www. mathsrevision. com Level 2 Learning Intention Success Criteria 1. We are learning that a factor divides into a number with no remainder 1. Identify factors using factor pairs 2. We are learning how to find Highest Common Factors 2. Find HCF for two numbers by comparing factors. 19 -Oct-21 Created by Mr. Lafferty

Types of Numbers Highest Common Factor www. mathsrevision. com Level 2 Example : Find the HCF of 8 and 12. F 8 = 1 and 8 F 12 = 1 and 12 2 and 4 2 and 6 3 and 4 HCF = 4 19 -Oct-21 Created by Mr. Lafferty

Types of Numbers Highest Common Factor www. mathsrevision. com Level 2 Highest Common Factor Largest Same Number We need to write out all factor pairs in order to find the Highest Common Factor. 19 -Oct-21 Created by Mr. Lafferty

Types of Numbers Factors www. mathsrevision. com Level 2 Example : Find the factors of 56. Always divide by 1 and find its pair F 56 = 1 and 56 From 2 find other factors and their pairs 2 and 28 4 and 14 7 and 19 -Oct-21 Created by Mr. Lafferty 8

www. mathsrevision. com Types of Numbers Now try Exercise 2 Ch 5 (page 30) 19 -Oct-21 Created by Mr. Lafferty

Starter Questions www. mathsrevision. com Level 2 4 cm 5 cm 19 -Oct-21 Created by Mr. Lafferty

Types of Numbers Prime Numbers www. mathsrevision. com Level 2 Learning Intention Success Criteria 1. We are learning what a prime number is. 1. understand the term Prime Number. 2. Find all prime between 1 and 200. 19 -Oct-21 Created by Mr. Lafferty

Types of Numbers Prime Numbers www. mathsrevision. com Level 2 Definition : A prime number is a number with exactly 2 factors. Example : Is 7 a prime number. Explain? Yes, only two factors 1, 7 Example : Is 10 a prime number. Explain? No, more than two factors 1, 2, 5, 10 19 -Oct-21 Created by Mr. Lafferty

Strike the two’s, strike three’s the Sieve of Eratosthenes 25 primes Below 100 when the multiples sublime, the numbers that remain are prime!

Use the method of Eratosthenes to find all primes below 200 What is the largest prime < 200? 46 primes below 200

Range 0 – 1000 – 2000 – 3000 – 4000 - 5000 - 6000 - 7000 – 8000 - 9000 – 10 000 – 11 000 – 12 000 Number of Primes 168 135 127 120 119 114 117 107 110 112 106 103 ?

Worksheet – www. mathsrevision. com Strike the two’s, strike three’s the Sieve of Eratosthenes when the multiples sublime, the numbers that remain are prime!

Types of Numbers www. mathsrevision. com Level 2 Now try Exercise 3 Ch 5 (page 32) 19 -Oct-21 Created by Mr. Lafferty

Starter Questions www. mathsrevision. com Level 2 5 cm 8 cm 119 19 -Oct-21 Created by Mr. Lafferty o

Types of Numbers Prime Decomposition www. mathsrevision. com Level 2 Learning Intention Success Criteria 1. We are learning what prime decomposition is. 1. Understand the term prime decomposition. 2. Decompose numbers to a product of prime only. 19 -Oct-21 Created by Mr. Lafferty

Types of Numbers Prime Decomposition www. mathsrevision. com Level 2 A number is either Prime or Composite. (except for 0) If it is composite, like 12, it can always be expressed as a “product of primes” Example : Express 12 as a “product of primes” 12 12 3 All Prime ! 19 -Oct-21 3 =3 x 4 4 2 2 Created by Mr. Lafferty =3 x 2 x 2

Types of Numbers Prime Decomposition Level 2 www. mathsrevision. com Example : Express 18 as a “product of primes” 18 18 3 All Prime ! 19 -Oct-21 3 =3 x 6 6 3 2 Created by Mr. Lafferty =3 x 3 x 2

Types of Numbers www. mathsrevision. com Level 2 Now try Exercise 4 Ch 5 (page 35) 19 -Oct-21 Created by Mr. Lafferty