BODMAS Why do we need BODMAS when you

BODMAS

Why do we need BODMAS ? when you see something like. . . 7 + (6 × 52 + 3). . . what part should you calculate first? Start at the left and go to the right? Or go from right to left? Calculate them in the wrong order, and you will get a wrong answer ! So, long ago people agreed to always follow certain rules when doing calculations. One of them is “BODMAS”

What is BODMAS ? n n n n Bracket = ( ) Orders or power Of = Powers and Square Roots, etc. Multiplication = × Division = ÷ Addition = + Subtraction = Other names for BODMAS = "Exponents" is used in Canada, and so you might prefer "BEDMAS". There is also "Indices" so that makes it "BIDMAS". In the US they say "Parenthesis" instead of Brackets, so they say "PEMDAS“.

How do I Remember ? BODMAS! n n B Brackets first O Orders (i. e. Powers and Square Roots, etc. ) DM Division and Multiplication (left-to-right) AS Addition and Subtraction (left-to-right)

Brackets n Brackets are Parenthesis ( ). n Brackets are used to group things. n This is the first thing you do in a question. n Do things in Brackets First. 6 × (5 + 3) = 6 × 8 = 48 6 × (5 + 3) = 30 + 3 = 33 (wrong)

Order or Exponents n n (Powers, Roots) before Multiply, Divide, Add or Subtract. Example Exponents are used to shorten the equation. If you see an exponent, you multiply the main number by itself that many times. Solve the Exponents first 5 × 22 = 5 × 4 = 20 5 × 22 = 100 (wrong)

Multiplication n In the Order of Operations, you would complete the equation left to right, doing which ever one appears first, Multiplication or Division. n The symbol for multiplication is ‘x’. n Remember to go from left to right. n Multiply or Divide before you Add or Subtract. 2 + 5 × 3 = 2 + 15 = 17 2 + 5 × 3 = 7 × 3 = 21 (wrong)

Division n In the Order of Operations, you would complete the equation left to right, doing which ever one appears first, Multiplication or Division. n Division is an equation that puts numbers in to groups. n The Division symbol is ÷ n Remember to go from left to right 30 ÷ 5 × 3 = 6 × 3 = 18 30 ÷ 5 × 3 = 30 ÷ 15 = 2(wrong)

Addition n In the Order of Operations, you would complete the equation left to right, doing which ever one appears first, Addition or Subtraction. n Addition is adding numbers together. n The symbol for addition is +. Example: 6 + 9 = 15

Subtraction n In the Order of Operations, you would complete the equation left to right, doing which ever one appears first, Addition or Subtraction. n Subtraction is taking away a specific number. n The symbol for subtraction is -. Example: 17 – 8 = 9

Summary BODMAS is a word which helps us to remember the order we do in a maths sum. operations brackets powers of It stands for first, then . multiplication division Next do or (it does not matter which way round you do these). addition subtraction Finally do or (again, it does not matter which way you do these. ) powers of Some people use the word Bidmas. In this case is indices replaced by , which means the same thing. Copy and fill in the gaps using the words below operations multiplication subtraction division brackets powers of addition

Sample Equation 4 × 3 + 6 - (12 ÷ 22 + 5) = 4 × 3 + 6 - (12 ÷ 4 + 5) = 4 × 3 + 6 - (3 + 5) = 4 × 3 + 6 - (8) = 12 + 6 – 8 = 10