How to do a PowerPoint PresentationWhen to use the “Order of Operations”
When there is more than one operation involved in a mathematical problem, it must be solved using the “Order of Operations”.
Why do you have to use it?
In Mathematics, the order in which mathematical problems are solved is extremely important to obtain the right answer.
If you are doing math operations by hand, with a calculator, or a software program, you have to follow the correct order of operations.
If you use a calculator, you will need to enter the operations in the correct order for the calculator to give you the right answer. Calculators, worksheets, and software programs will perform operations in the order which you enter them; therefore, you will need to enter the operations in the correct order to obtain the right answer.
Order of Operations’ Rules
1. Calculations must be done from left to right.
2. Calculations in brackets (parenthesis) are done first. When you have more than one set of brackets, do the inner brackets first.
3. Exponents (or radicals) must be done next.
4. Multiply and divide in the order the operations occur from left to right.
5. Add and subtract in the order the operations occur from left to right.
Example:
100 ÷ 5 - (3 X (25 ÷ 5)) + 42 X 3 =
First Step: We use the Second Rule. Calculations in brackets (parenthesis) are done first. When you have more than one set of brackets, do the inner brackets first. (25 ÷ 5) = 5
We have now: 100 ÷ 5 - (3 X 5) + 42 X 3 =
Continuing with the example…
We have now: 100 ÷ 5 - (3 X 5) + 42 X 3 =
Second Step: We use the Second Rule again. Calculations in brackets (parenthesis) are done first. When you have more than one set of brackets, do the inner brackets first. 3 X 5 =15
Now we have: 100 ÷ 5 - 15 + 42 X 3 =
Continuing with the example…
We have now: 100 ÷ 5 - 15 + 42 X 3 =
Third step: We use the Third Rule Exponents (or radicals) must be done next. 42 = 16
Now we have: 100 ÷ 5 - 15 + 16 X 3 =
Continuing with the example…
We have now: 100 ÷ 5 - 15 + 16 X 3 =
Fourth Step: We use the Fourth Rule. Multiply and divide in the order the operations occur from left to right. From left to right, the first operation is: 100 ÷ 5 = 20 Then, continuing from left to right, the next operation that we find is 16 X 3 = 48
Now we have: 20 – 15 + 48 =
Continuing with the example…
We have now: 20 – 15 + 48 =
Fifth Step: We use the Fifth Rule. Add and subtract in the order the operations occur from left to right. From left to right, the first operation is: 20 - 5 = 5
Finally we have: 5 + 48 = 53
An Easy Way to Remember the Order of Operations
Try the following Acronym:
PEMDAS Please Excuse My Dear Aunt Sally  (Parenthesis, Exponents, Multiply, Divide, Add, Subtract)
Do not Forget to Practice
Thanks for your attention
Have a nice weekend!!!