Exercise 2 Page 39

According to the order of operations, operations in grouping symbols are evaluated first, followed by exponents, then multiplication and division, and finally addition and subtraction are evaluated last. We can use the acronym PEMDAS to help us remember the correct order!

We want to determine a equivalent number for the given expression. 3* 2^3 - 8 ÷ 4 To do so, we will evaluate it by following the order of operations. Let's do it!

Operation	Before Simplification	After Simplification
Calculate power	3* 2^3 - 8 ÷ 4	3* 8 - 8 ÷ 4
Multiply	3* 8 - 8 ÷ 4	24 - 8 ÷ 4
Divide	24 - 8 ÷ 4	24- 2
Subtract terms	24- 2	22

The expression is equal to 22. Therefore, the correct option is C.

Alternative Solution

Using a Calculator

We can also evaluate this expression using a calculator. To do so, we type it as shown below.

Whenever using a calculator for a complicated expression such as this, be very careful when placing the parentheses. A calculator will only do what it is told to do, not what you meant for it do.