BIDMAS ORDER OF OPERATIONS Objectives By the end

BIDMAS ORDER OF OPERATIONS

Objectives By the end of this lesson learners will be able to: • Understand the order of operations of BIDMAS • Identify the Lowest Common Multiple of a number • Identify the Highest Common Factor of a number

1 2 3 4 BIDMAS BRACKETS 1 INDICES 2 DIVIDE or MULTIPLY 3 in the order that they come ADD or SUBTRACT 4 in the order that they come

Example 1 BIDMAS 2+3 4 = 2 + 12 M = 14 A

Example 2 BIDMAS 2+3 4 2 = 2 + 12 2 M =2+6 =8 D A

Example 3 BIDMAS 2 3 - ( 4 + 2) =2 3 - 6 =6 -6 =0 B M S

Example 4 BIDMAS 2 3² - ( 4 + 2) B = 2 3² - 6 I = 2 9 - 6 = 18 - 6 = 12 M S

Example 5 BIDMAS = (25× 4) (48+2) = 100 50 =2 D B

Identify the prime numbers in the grid below. There are 7 to find. 39 45 X 22 X 23 X 63 17 9 57 81 X X 11 77 27 X X 19 99 X X 37 X 1 69 X 2 49 7

Lowest Common Multiple (LCM) • Lowest Common Multiple – the lowest number in two or more numbers’ times tables.

Lowest Common Multiple (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

Lowest Common Multiple (LCM) • Find the LCM of 12 and 8.

Lowest Common Multiple (LCM) Find the LCM of the following: a) 2 and 5 e) 3 and 8 b) 3 and 4 f) 4 and 9 c) 4 and 8 g) 8 and 10 10 12 8 d) 5 and 6 30 24 36 40 h) 4, 5 and 12. 60

Highest Common Factor (HCF) • Highest Common Factor (HCF) – the largest number that goes into two or more numbers exactly. • Example: Find the HCF of 32 and 56 32 1, 2, 4, 8, 16, 32 56 1, 2, 4, 7, 8, 14, 28, 56 HCF = 8

Highest Common Factor (HCF) Find the HCF of the following numbers: a) 8 and 12 4 b) 9 and 15 3 c) 10 and 30 10 d) 18 and 33 3 e) 32 and 80 16 f) 60 and 108 12 g) 36, 64, and 76 4 e) 48, 60 and 84 12