Lesson 9 Factors, Multiples, Primes and Squares. Mathswatch
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GCSE Maths Starter 9 2.Expand 5(x 3) 3.Simplify y x y 4.What is
304 8 5.What is 60C converted into F? 1) Describe the Correlation
in the scatter graph below..
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To identify factors, multiples, squares and prime numbers To
find the prime factor decomposition of positive integers To find
the Highest Common Factor (HCF) and the Least Common Multiple (LCM)
of two numbers EXTN: To solve real life problems involving HCF and
LCM.(Grade C) Lesson 9 Factors, Multiples, Primes and Squares.
Mathswatch 44/95/96
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What are the first five multiples of: a)3 b)4 c)11 d)21 3, 6,
9, 12, 15 4, 8, 12, 16, 20 11, 22, 33, 44, 55 21, 42, 63, 82, 105 A
multiple of a number is what you get when you multiply that number
by some other whole number. Multiples are Usually Larger Than
Individual numbers, Possibly Larger never Ever Smaller Lesson 9
Factors, Multiples, Primes and Squares. Mathswatch 44/95/96
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7 11 19 23 2 17 3749 9 2245 63 5781 27 69 77 99 1 X 7 23 17 11
19 X X 2 XX X X X XXX X X 37 39 Identify the prime numbers in the
grid below. There are 7 to find. Lesson 9 Factors, Multiples,
Primes and Squares. Mathswatch 44/95/96
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Lowest Common Multiple the lowest number in two or more numbers
times tables. Q. Find the LCM of 4 and 6. 1.Write out the first six
numbers the 4 and 6 times tables 2.Look for the first number that
appears in both lists. Lesson 9 Factors, Multiples, Primes and
Squares. Mathswatch 44/95/96
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Example LCM Q.Find the LCM of 4 and 6 4 4, 8, 12, 16, 20, 24,.
6 6, 12, 18, 24, 30, 36, We want the LOWEST common multiple, so the
LCM of 4 and 6 is 12 Lesson 9 Factors, Multiples, Primes and
Squares. Mathswatch 44/95/96
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a)2 and 5 b)3 and 4 c)4 and 8 d)5 and 6 e)3 and 8 f)4 and 9 g)8
and 10 h)4, 5 and 12. 10 12 8 30 24 36 40 60 Find the LCM of the
following: Lesson 9 Factors, Multiples, Primes and Squares.
Mathswatch 44/95/96
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What are the factors of: a)16 b)30 c)8 d)7 1, 2, 4, 8, 16 1, 2,
5, 6, 15, 30 1, 2, 4, 8 1, 7 A factor is a whole number which
divides exactly into a whole number, leaving no remainder. Factors
Are Certainly Tiny Or Really Small A prime number has exactly two
factors: 1, and the number itself. Lesson 9 Factors, Multiples,
Primes and Squares. Mathswatch 44/95/96
a)8 and 12 b)9 and 15 c)10 and 30 d)18 and 33 e)32 and 80 f)60
and 108 g)36, 64, and 76 h)48, 60 and 84 Find the HCF of the
following numbers: 4 3 10 3 16 12 4 Lesson 9 Factors, Multiples,
Primes and Squares. Mathswatch 44/95/96
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We can use a factor tree to enable us to write a number as a
product of its prime factors Each time you reach a prime number,
you stop and circle that number. Lesson 9 Factors, Multiples,
Primes and Squares. Mathswatch 44/95/96
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Example: Write 84 as a product of its prime factors 84 = 2 x 2
x 3 x 7 84 = 2 2 x 3 x 7 Now your turn: Write 42 as a product of
prime factors. 84 242 221 37 Lesson 9 Factors, Multiples, Primes
and Squares. Mathswatch 44/95/96
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Your turn 1.Find the HCF of the following: a)18 and 28 b)16 and
40 c)42 and 90 d)40 and 63 e)20, 64 and 108 f)54, 90 and 162 2.Find
the LCM of the following: a)4 and 5 b)8 and 12 c)6 and 9 d)12 and
15 e)5, 8 and 10 f)4, 7 and 9 3.Write the following as products of
their prime factors. a) 18b) 135c) 154d) 2310 2 8 6 1 4 18 20 24 18
60 40 252 3 2 x 2 3 3 x 5 2 x 7 x 11 2 x 3 x 5 x 7 x 11
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To identify factors, multiples, squares and prime numbers To
find the prime factor decomposition of positive integers To find
the Highest Common Factor (HCF) and the Least Common Multiple (LCM)
of two numbers EXTN: To solve real life problems involving HCF and
LCM.(Grade C) Lesson 9 Factors, Multiples, Primes and Squares.
Mathswatch 44/95/96