Parentheses and Order of Operations

We use parentheses when we want to do arithmetic operations in a different order than MDAS. This means that the main purpose of the parentheses is to allow you to add and subtract before you multiply and divide.

Before you get to look at combined problems, I’ll teach you how parentheses work.

• Multiple numbers inside parentheses: Add the numbers to each other:

  $$(2+3)=(5)=5$$

• A number multiplied by parentheses with numbers inside: Solve the expression inside the parentheses, then multiply by the number outside:

  $$3(4+2)=3(6)=18$$

• Parentheses multiplied by parentheses: Solve the expression inside each of the parentheses, then multiply the remaining numbers with each other:

  $$(3+6)(5+1)=(9)(6)=54$$

• A number multiplied by parentheses multiplied by another parentheses: Solve the expression inside of each of the parentheses, then multiply the remaining numbers by each other:

  $$2(4+1)(7+3)=2(5)(10)=100$$