Order of Operation Practice Questions, Rules, Examples & Review

The order of operation rules are:

Rule 1: Start with calculations inside brackets or parentheses.
Rule 2: Then, solve multiplications and division, from left to right.
Rule 3: Finally, additions and subtraction, from left to right.

Example 1

Solve 16 + 5 x 8

Based on the rules above, start with multiplication.

This gives: 16 + 40 = 56

Note that if the rule was not followed, and addition was done first, the answer would be different and incorrect, as in,

16 + 5 x 8

21 x 8 = 168 (wrong answer)

Example 2

3 +(35 – 21) x 2

Solve the problem inside the brackets first. Then multiplication, and finally addition.

3 + (35 – 21) x 2
3 + (14) x 2
3 + 28
= 31

Misinterpreting PEMDAS. The PEMDAS rule is (Parentheses, Exponents, Multiplication/Division, Addition/Subtraction). This can be misinterpreted as a strict order of operations where multiplication must always be done before division, which is incorrect. The rule actually says to perform operations within parentheses first and then applying the other operations in order from left to right.

Errors with multiplication and division. Multiplication and division have equal precedence and should be performed from left to right. Assuming multiplication should always be done before division, is incorrect.

Not simplifying fractions. Always simplify them before performing other operations.

10 Comments

Gavin

June 4, 2017

BIMDAS rule. Easy to remember.

Brian

I think it is PIMDAS – Parentheses, Exponents, Multiplication, Division, Addition, Subtraction. … The original order of operations in some countries was BODMAS, which stands for Brackets, Orders or Powers, Division, Multiplication, Addition, Subtraction.

Anonymous

June 20, 2017

Thank you!

January 27, 2018

BEDMAS=brackets, exponents, division, multiplication, addition then subtracting

June 4, 2018

PEMDAS:
Please (Parentheses)
Excuse (Exponents)
My (Mult.)
Dear (Div.)
Aunt (Addition)
Sally (Subtraction)

June 5, 2018

Very Good!

August 20, 2018

Thanks for sharing this!

Ryan Wildes

August 29, 2018

I am useless with mathematics but need to practice before I start a nursing degree. Thanks for explaining how to do these kind of sums, helped me a lot.

October 14, 2018

GEMS
Groupings
Exponents/Square Roots
Multiplication/Division
Subtraction/Addition

Each one you do you also have to do the opposite item at the same time.

December 7, 2021

BODMAS…….. bracket off division multiplication addition and subtraction

Math

Basic Math – Order of Operation Practice & Tutorial

Order of Operation – Rules, Examples and Practice Questions

Example 1

Example 2