Need Advice What Is BODMAS Rule
- Thread starter angrythor
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Look here
www.purplemath.com
What is the order of operations? Why do we need it?
The order of operations is parentheses (simplify inside 'em), exponents (apply 'em), multiply/divide (left to right), & add/subtract (left to right).
www.purplemath.com
HallsofIvy
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"BODMAS" is an acronym used primarily in Britain to remember the order of arithmetic operations.
B: Brackets
O: Order
D: Division
M: Multiplication
A: Addition
S: Subtraction
That is, anything inside brackets (or parentheses) is done first. "Orders" (or "powers") are done next, then division and multiplication (which actually can be done in either order) then addition and subtraction (which also can be done in either order). For example, 3*4+ 5 would be done as "first 3*4= 12 then add 5 to get 17" since "M", multiplication, comes before "A", addition. But 3(4+ 5) would be done as "first 4+ 5= 9 then multiply by 3 to get 27" because the "4+ 5" is inside parentheses. To do 3*4+ 5^2 we would first calculate 5^2= 25, since the "O", "order" or "power" 2, comes first. Then we calculate 3*4= 12, and, last, add, 12+ 25= 37 since "M", "multiplication" comes before "A", addition. But (3*4+ 5)^2= 17^2= 289 because the calculation inside the parentheses is completed first.
In the United States we tend to use "PEMDAS" (remembered as the mnemonic "Please Excuse My Dear Aunt Sally")- Parentheses, exponents, multiplication, division, addition, subtraction,
B: Brackets
O: Order
D: Division
M: Multiplication
A: Addition
S: Subtraction
That is, anything inside brackets (or parentheses) is done first. "Orders" (or "powers") are done next, then division and multiplication (which actually can be done in either order) then addition and subtraction (which also can be done in either order). For example, 3*4+ 5 would be done as "first 3*4= 12 then add 5 to get 17" since "M", multiplication, comes before "A", addition. But 3(4+ 5) would be done as "first 4+ 5= 9 then multiply by 3 to get 27" because the "4+ 5" is inside parentheses. To do 3*4+ 5^2 we would first calculate 5^2= 25, since the "O", "order" or "power" 2, comes first. Then we calculate 3*4= 12, and, last, add, 12+ 25= 37 since "M", "multiplication" comes before "A", addition. But (3*4+ 5)^2= 17^2= 289 because the calculation inside the parentheses is completed first.
In the United States we tend to use "PEMDAS" (remembered as the mnemonic "Please Excuse My Dear Aunt Sally")- Parentheses, exponents, multiplication, division, addition, subtraction,
