ALWAYS REMEMBER TO: PLEASE EXCUSE MY DEAR AUNT SALLY.

•ALWAYS REMEMBER TO:•PLEASE•EXCUSE•MY DEAR•AUNT SALLY

ALWAYS follow this order:• Parentheses• Exponent •Multiply or Divide (from left

to right)• Add or Subtract (from left to

right)

Let’s practice. What is the order?

• ()•X²•x or ÷•+ or -

KEY CONCEPTS1. Do every expression within the

parentheses (in order).2. Find the value of all powers.3. Multiply or divide in order from

left to right.4. Add or subtract in order from

left to right.

Now, let’s look at a problem two different ways…This will prove why

order IS important.

5 + 3 x 28 x 2 = 16

This is NOT correct. The correct order of

operations has not been followed. Let’s

do this problem correct!

Now, let’s sing a little song sung to the tune of “Deck the Halls”

Sung to the tune of “Deck the Halls”

Please excuse my dear Aunt SallyThis is the order of operationsParenthesesThen the exponentThis is the order that it goes…Multiply or DivideDo this in order from left to rightThen you add or subtractDo this also from left to right.Please excuse my dear Aunt SallyThis is the order in which it goes.

Let’s practice.

Note to teacher: You can work the following problems on the board, Elmo, whiteboards, etc. Students can even work it out on the TV screen with a dry erase marker)

(11-7) x 3 - 5

Answer: 7

6 x 8 + 4 ÷ 2

Hint: Multiply, then divide, next, add.

Answer: 50

Here’s a challenge!

96 ÷ 4² + (25 x 2) - 15 - 3 Hints:• Solve the

parentheses• Don’t forget the

exponent• Next divide• Then add• If you have two of

the same operation (subtraction) do those from left to right

Answer: 38

Here’s one more without hints.

27 ÷ (3 + 6) x 5 - 12

Answer: 3

The most important thing to remember is

order order

ORDER