1. Home
  2. Contemporary math applications
  3. Helpful topics
  4. Whole numbers
  5. Whole numbers: order of operations

7.6 Whole numbers: order of operations  (Page 2/2)

<< Chapter < Page
  Contemporary math applications     Page 2 / 2
Chapter >> Page >

Add 3 and 5, then multiply this sum by 2.

  3 + 5 ⋅ 2 = 8 ⋅ 2 = 16 alignl { stack { size 12{`3+5 cdot 2} {} #size 12{`=8 cdot 2} {} # size 12{`="16"} {}} } {}

Multiply 5 and 2, then add 3 to this product.

  3 + 5 ⋅ 2 = 3 + 10 = 13 alignl { stack { size 12{`3+5 cdot 2} {} #size 12{`=3+"10"} {} # size 12{`="13"} {}} } {}

We now have two values for the same expression.

We need a set of rules to guide anyone to one unique value for this kind of expression. Some of these rules are based on convention, while other are forced on up by mathematical logic.

The universally agreed-upon accepted order of operations for evaluating a mathematical expression is as follows:

1. Parentheses (grouping symbols) from the inside out.

By parentheses we mean anything that acts as a grouping symbol, including anything inside symbols such as [  ], {  }, |  |, and size 12{` sqrt {`} } {} . Any expression in the numerator or denominator of a fraction or in an exponent is also considered grouped, and should be simplified before carrying out further operations.

If there are nested parentheses (parentheses inside parentheses), you work from the innermost parentheses outward.

2. Exponents and other special functions, such as log, sin, cos etc.

3. Multiplications and divisions, from left to right.

4. Additions and subtractions, from left to right.

For example, given: 3 + 15 ÷ 3 + 5 × 2 2+3

The exponent is an implied grouping, so the 2+3 must be evaluated first:

 = 3 + 15 ÷ 3 + 5 × 2 5

Now the exponent is carried out:

 = 3 +15 ÷ 3 + 5 × 32

Then the multiplication and division, left to right using 15 ÷ 3 = 5 and 5 × 32 = 160:

 = 3 + 5 + 160

Finally, the addition, left to right:

 = 168

Examples, order of operation

Determine the value of each of the following.

21 + 3 ⋅ 12 size 12{"21"+3 cdot "12"} {} .

Multiply first:

= 21 + 36 size 12{"21"+"36"} {}

Add.

= 57

  

( 15 − 8 ) + 5 ( 6 + 4 ) size 12{ \( "15" - 8 \) +5 \( 6+4 \) } {} .

Simplify inside parentheses first.

= 7 + 5 ⋅ 10 size 12{7+5 cdot "10"} {}

Multiply.

= 7 + 50 size 12{7+"50"} {}

Add.

= 57

  

63 − ( 4 + 6 ⋅ 3 ) + 76 − 4 size 12{"63" - \( 4+6 cdot 3 \) +"76" - 4} {} .

Simplify first within the parentheses by multiplying, then adding:

= 63 − ( 4 + 18 ) + 76 − 4 size 12{"63" - \( 4+"18" \) +"76" - 4} {}

= 63 − 22 + 76 − 4 size 12{"63" - "22"+"76" - 4} {}

Now perform the additions and subtractions, moving left to right:

= 41 + 76 − 4 size 12{"41"+"76" - 4} {}

= 117 − 4 size 12{"117" - 4} {}

= 113.

  

7 ⋅ 6 − 4 2 + 1 5 size 12{7 cdot 6 - 4 rSup { size 8{2} } +1 rSup { size 8{5} } } {}

Evaluate the exponential forms, moving from left to right:

= 7 ⋅ 6 − 16 + 1 size 12{7 cdot 6 - "16"+1} {}

Multiply 7 · 6:

= 42 − 16 + 1 size 12{"42" - "16"+1} {}

Subtract 16 from 42:

= 26 + 1

Add 26 and 1:

= 27.

  

6 ⋅ ( 3 2 + 2 2 ) + 4 2 size 12{6 cdot \( 3 rSup { size 8{2} } +2 rSup { size 8{2} } \) +4 rSup { size 8{2} } } {}

Evaluate the exponential forms in the parentheses:

= 6 ⋅ ( 9 + 4 ) + 4 2 size 12{6 cdot \( 9+4 \) +4 rSup { size 8{2} } } {}

Add 9 and 4 in the parentheses:

= 6 ⋅ ( 13 ) + 4 2 size 12{6 cdot \( "13" \) +4 rSup { size 8{2} } } {}

Evaluate the exponential form 4 2 size 12{4 rSup { size 8{2} } } {} :

= 6 ⋅ ( 13 ) + 16 size 12{6 cdot \( "13" \) +"16"} {}

Multiply 6 and 13:

= 78 + 16 size 12{"78"+"16"} {}

Add 78 and 16:

= 94

  

6 2 + 2 2 4 2 + 6 ⋅ 2 2 + 1 3 + 8 2 10 2 − 19 ⋅ 5 size 12{ { {6 rSup { size 8{2} } +2 rSup { size 8{2} } } over {4 rSup { size 8{2} } +6 cdot 2 rSup { size 8{2} } } } + { {1 rSup { size 8{3} } +8 rSup { size 8{2} } } over {"10" rSup { size 8{2} } - "19" cdot 5} } } {} .

= 36 + 4 16 + 6 ⋅ 4 + 1 + 64 100 − 19 ⋅ 5 size 12{ { {"36"+4} over {"16"+6 cdot 4} } + { {1+"64"} over {"100" - "19" cdot 5} } } {}

= 36 + 4 16 + 24 + 1 + 64 100 − 95 size 12{ { {"36"+4} over {"16"+"24"} } + { {1+"64"} over {"100" - "95"} } } {}

= 40 40 + 65 5 size 12{ { {"40"} over {"40"} } + { {"65"} over {5} } } {}

= 1+13

= 14

Recall that the bar is a grouping symbol. The fraction 6 2 + 2 2 4 2 + 6 ⋅ 2 2 size 12{ { {6 rSup { size 8{2} } +2 rSup { size 8{2} } } over {4 rSup { size 8{2} } +6 cdot 2 rSup { size 8{2} } } } } {} is equivalent to 6 2 + 2 2 ÷ 4 2 + 6 ⋅ 2 2 size 12{ left (6 rSup { size 8{2} } +2 rSup { size 8{2} } right ) div left (4 rSup { size 8{2} } +6 cdot 2 rSup { size 8{2} } right )} {}

Exercises, order of operations

Determine the value of the following:

8 + (32 – 7)

66

(34 + 18 – 2 · 3) + 11

57

8(10) + 4(2 + 3) – (20 + 3 · 15 + 40 – 5)

0

5 · 8 + 42 – 22

52

4(6 2 – 3 3 ) ÷ (4 2 – 4)

9

(8 + 9 · 3) ÷ 7 + 5 · (8 ÷ 4 + 7 + 3 · 5)

125

3 3 + 2 3 6 2 − 29 + 5 8 2 + 2 4 7 2 − 3 2 ÷ 8 ⋅ 3 + 1 8 2 3 − 3 size 12{ { {3 rSup { size 8{3} } +2 rSup { size 8{3} } } over {6 rSup { size 8{2} } - "29"} } +5 left ( { {8 rSup { size 8{2} } +2 rSup { size 8{4} } } over {7 rSup { size 8{2} } - 3 rSup { size 8{2} } } } right ) div { {8 cdot 3+1 rSup { size 8{8} } } over {2 rSup { size 8{3} } - 3} } } {}

7

Module review exercises

For the following problems, find each value.

2 + 3 ⋅ ( 8 ) size 12{2+3 cdot \( 8 \) } {}

48

1 − 5 ( 8 − 8 ) size 12{1 - 5 \( 8 - 8 \) } {}

meaningless

37 − 1 ⋅ 6 2 size 12{"37" - 1 cdot 6 rSup { size 8{2} } } {}

1

98 ÷ 2 ÷ 7 2 size 12{"98" div 2 div 7 rSup { size 8{2} } } {}

1

( 4 2 − 2 ⋅ 4 ) − 2 3 size 12{ \( 4 rSup { size 8{2} } - 2 cdot 4 \) - 2 rSup { size 8{3} } } {}

0

61 − 22 + 4 [ 3 ⋅ ( 10 ) + 11 ] size 12{"61" - "22"+4 \[ 3 cdot \( "10" \) +"11" \] } {}

203

121 − 4 ⋅ [ ( 4 ) ⋅ ( 5 ) − 12 ] + 16 2 size 12{"121" - 4 cdot \[ \( 4 \) cdot \( 5 \) - "12" \] + { {"16"} over {2} } } {}

97

2 2 ⋅ 3 + 2 3 ( 6 − 2 ) − ( 3 + 17 ) + 11 ( 6 ) size 12{2 rSup { size 8{2} } cdot 3+2 rSup { size 8{3} } \( 6 - 2 \) - \( 3+"17" \) +"11" \( 6 \) } {}

90

8 ( 6 + 20 ) 8 + 3 ( 6 + 16 ) 22 size 12{ { {8 \( 6+"20" \) } over {8} } + { {3 \( 6+"16" \) } over {"22"} } } {}

29

( 1 + 16 ) − 3 7 + 5 ( 12 ) size 12{ { { \( 1+"16" \) - 3} over {7} } +5 \( "12" \) } {}

62

1 6 + 0 8 + 5 2 ( 2 + 8 ) 3 size 12{1 rSup { size 8{6} } +0 rSup { size 8{8} } +5 rSup { size 8{2} } \( 2+8 \) rSup { size 8{3} } } {}

25,001

5 ( 8 2 − 9 ⋅ 6 ) 2 5 − 7 + 7 2 − 4 2 2 4 − 5 size 12{ { {5 \( 8 rSup { size 8{2} } - 9 cdot 6 \) } over {2 rSup { size 8{5} } - 7} } + { {7 rSup { size 8{2} } - 4 rSup { size 8{2} } } over {2 rSup { size 8{4} } - 5} } } {}

5

6 { 2 ⋅ 8 + 3 } − ( 5 ) ⋅ ( 2 ) + 8 4 + ( 1 + 8 ) ⋅ ( 1 + 11 ) size 12{6 lbrace 2 cdot 8+3 rbrace - \( 5 \) cdot \( 2 \) + { {8} over {4} } + \( 1+8 \) cdot \( 1+"11" \) } {}

214

26 − 2 ⋅ 6 + 20 13 size 12{"26"` - `2` cdot ` left lbrace { {6+"20"} over {"13"} } right rbrace } {}

22

( 10 + 5 ) ⋅ ( 10 + 5 ) − 4 ⋅ ( 60 − 4 ) size 12{ \( "10"+5 \) ` cdot ` \( "10"+5 \) ` - `4 cdot \( "60" - 4 \) } {}

1

6 2 − 1 2 3 − 3 + 4 3 + 2 ⋅ 3 2 ⋅ 5 size 12{ { {6 rSup { size 8{2} } - 1} over {2 rSup { size 8{3} } - 3} } `+` { {4 rSup { size 8{3} } +2` cdot `3} over {2` cdot `5} } } {}

14

51 17 + 7 − 2 ⋅ 5 ⋅ 12 3 size 12{ { {"51"} over {"17"} } `+`7` - `2` cdot `5` cdot ` left ( { {"12"} over {3} } right )} {}

-30

( 21 − 3 ) ⋅ ( 6 − 1 ) ⋅ 6 + 4 ( 6 + 3 ) size 12{ \( "21" - 3 \) ` cdot ` \( 6 - 1 \) ` cdot ` left (6 right )+4 \( 6+3 \) } {}

576

( 2 + 1 ) 3 + 2 3 + 1 10 6 2 − 15 2 − [ 2 ⋅ 5 ] 2 5 ⋅ 5 2 size 12{ { { \( 2+1 \) rSup { size 8{3} } +2 rSup { size 8{3} } +1 rSup { size 8{"10"} } } over {6 rSup { size 8{2} } } } ` - ` { {"15" rSup { size 8{2} } - \[ 2` cdot `5 \] rSup { size 8{2} } } over {5` cdot `5 rSup { size 8{2} } } } } {}

0

Questions & Answers

what is biology
Hajah Reply
the study of living organisms and their interactions with one another and their environments
AI-Robot
what is biology
Victoria Reply
HOW CAN MAN ORGAN FUNCTION
Alfred Reply
the diagram of the digestive system
Assiatu Reply
allimentary cannel
Ogenrwot
How does twins formed
William Reply
They formed in two ways first when one sperm and one egg are splited by mitosis or two sperm and two eggs join together
Oluwatobi
what is genetics
Josephine Reply
Genetics is the study of heredity
Misack
how does twins formed?
Misack
What is manual
Hassan Reply
discuss biological phenomenon and provide pieces of evidence to show that it was responsible for the formation of eukaryotic organelles
Joseph Reply
what is biology
Yousuf Reply
the study of living organisms and their interactions with one another and their environment.
Wine
discuss the biological phenomenon and provide pieces of evidence to show that it was responsible for the formation of eukaryotic organelles in an essay form
Joseph Reply
what is the blood cells
Shaker Reply
list any five characteristics of the blood cells
Shaker
lack electricity and its more savely than electronic microscope because its naturally by using of light
Abdullahi Reply
advantage of electronic microscope is easily and clearly while disadvantage is dangerous because its electronic. advantage of light microscope is savely and naturally by sun while disadvantage is not easily,means its not sharp and not clear
Abdullahi
cell theory state that every organisms composed of one or more cell,cell is the basic unit of life
Abdullahi
is like gone fail us
DENG
cells is the basic structure and functions of all living things
Ramadan
What is classification
ISCONT Reply
is organisms that are similar into groups called tara
Yamosa
in what situation (s) would be the use of a scanning electron microscope be ideal and why?
Kenna Reply
A scanning electron microscope (SEM) is ideal for situations requiring high-resolution imaging of surfaces. It is commonly used in materials science, biology, and geology to examine the topography and composition of samples at a nanoscale level. SEM is particularly useful for studying fine details,
Hilary
cell is the building block of life.
Condoleezza Reply
Got questions? Join the online conversation and get instant answers!
Jobilize.com Reply
<< Chapter < Page Page > Chapter >>

Read also:

Get Jobilize Job Search Mobile App in your pocket Now!

Get it on Google Play Download on the App Store Now




Source:  OpenStax, Contemporary math applications. OpenStax CNX. Dec 15, 2014 Download for free at http://legacy.cnx.org/content/col11559/1.6
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Contemporary math applications' conversation and receive update notifications?

Ask