Pre-Algebra - Order of Operations

Simplify:

Explanation

Follow the order of operations: parentheses, exponents, multiplication, division, addition, and subtraction. Work from left to right, and start with the innermost nested operations when dealing with multiple parentheses:

Select the equation that reflects the phrase below.

First add and , then multiply by .

$(8+9)\times2$

$(18+9)\times2$

$8+9\times2$

$2\times8+9$

$2\times9+8$

Explanation

Because we want to add and first, we need to set that off into parentheses due to the order of operation rules. Then we can multiply by .

Solve:

$2\times (50-25)\div5$

Explanation

$2\times (50-25)\div5$

When solving this problem, remember order of operations PEMDAS. The parentheses come first, followed by the multiplication, and then the division.

$25\times2=50$

$50\div5=10$

Simplify:

Explanation

Solve using the order of operations:

$9 \cdot 3^2 + 12 \div 3$

Explanation

The order of operations is the order in which you must solve a problem. The order is defined as

PARENTHESES

EXPONENTS

MULTIPLICATION

DIVISION

ADDITION

SUBTRACTION

where we solve parentheses first, followed by exponents, and so on. Following the order of operations, we get

$9 \cdot 3^2 + 12 \div 3$

$9 \cdot 9 + 12 \div 3$

$81 + 12 \div 3$

Evaluate

$4+6\div2$

Explanation

When doing multiple operations, always remember PEMDAS. There is division and addition. D comes first and is the division so we do that first followed by addition. So we have $4+6\div2=4+3=7$ .