20
1 CHAPTER 1 INTRODUCTION 1. The Background Numbers almost relate to every human life side. Donna and Lawrence (1980:1) said that it is almost impossible to relate the real world without encountering numbers in one way or another, for example : money, time, quantities of objects, distance, etc. By studying mathematics we will know all about numbers, one of them is about number operations. Number operations are basic knowledge should be understood because in daily activites we always do counting. The ability to count is also necessary to be able to master others topics in mathematics. Therefore, these number operations are learned in elementary school. Basically, number operations consist of 4 operations, they are addition, subtraction, multiplication, and division. 2. The Purpose The purpose of this paper is in order to readers know and understand about: a. The number operations include addition, subtraction, multiplication, and division; b. The properties of number operations. c. The Bases of Number Ever Used d. The History of Months

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1�

CHAPTER 1

INTRODUCTION

1. The Background

Numbers almost relate to every human life side. Donna and Lawrence

(1980:1) said that it is almost impossible to relate the real world without

encountering numbers in one way or another, for example : money, time,

quantities of objects, distance, etc. By studying mathematics we will know all

about numbers, one of them is about number operations. Number operations are

basic knowledge should be understood because in daily activites we always do

counting. The ability to count is also necessary to be able to master others topics

in mathematics. Therefore, these number operations are learned in elementary

school. Basically, number operations consist of 4 operations, they are addition,

subtraction, multiplication, and division.

2. The Purpose

The purpose of this paper is in order to readers know and understand

about:

a. The number operations include addition, subtraction, multiplication, and

division;

b. The properties of number operations.

c. The Bases of Number Ever Used

d. The History of Months

2�

CHAPTER 2

DISCUSSION

1. Number Operations

There are 4 kinds of operations in mathematics include Addition,

Subtraction, Multiplication, and Division.

a. Addition

Addition is the process of combining two or more numbers and arriving at

a single total (Berston and Fisher, 1982). Furthermore, Berston and Fisher (1982)

said that the numbers to be added are called addends and the final result of the

addition is called the total, sum or amount. The addition symbol is written by “+”

and it is read “plus” or “add” (Ashlock, et.al. 1983:68). It first appeard in 1456 in

an unpublished manuscript by the mathematician Johann Regiomontanus.

Example :

4 + 7 + 11 is read as 4 plus 7 plus 11, and the sum is 22.

Example :

1. Simplify 5 + 1

To model this expression, we first hop 5 units to the right. Then we hop 1 unit

to the right. Since we end up on 6, the answer is 6.

5 + 1 = 6

2. Simplify 5 + (-2)

To model this problem, we hop 5 units to the right. The second hop is 2 units

to the left (please see note below). Since we end up on 3, the answer is 3.

��������

3�

5 + (-2) = 3

3. Simplify 5 + (-8)

To model this expression, we begin with a 5-unit hop to the right. The we hop

8 units to the left. Since 8 is bigger than 5, we cross over the 0 into the

negative side of the number line. We end up at -3, so the answer is -3.

5 + (-8) = -3

4. Simplify (-8) + 5

Since addition is commutative, (-8) + 5 should result in the same answer as

the previous example 5 + (-8). The model of (-8) + 5 means a hop of 8 units

to the left followed by a hop of 5 units to the right resulting in the same sum

as the previous example.

(-8) + 5 = -3

5. Simplify (-6) + 10

To model this expression, we begin by hopping 6 units to the left. Then we

hop 10 units to the right. Since we end up at 4, the answer is 4.

4�

(-6) + 10 = 4

6. Simplify: (-6) + (-2)

To model this problem, we make two hops to the left. The first hop is 6 units

to the left. Then we hop 2 units to the left. We end up at -8.

(-6) + (-2) = -8

7. Simplify: (-10) + (-5)

To model this expression, we make a 10-unit hop to the left, followed by a 5-

unit hop to the left.

b. Subtraction

Subtraction is the process of finding the difference between two amounts

(Berston and Fisher, 1982). There are three parts in subtraction, they are minuend,

subtrahend and difference. Minuend is a number from which another is subtracted.

It is the first number in subtraction. Subtrahend is the amount that is subtracted

from another (minuend) while the result of subtraction is called the remainder or

difference. It first appeard in 1456 in an unpublished manuscript by the

mathematician Johann Regiomontanus. Ashlock, et. al. (1983:72) said that

subtraction is the inverse of addition. Addition is used to find the sum when its

addends are known, while subtraction is used to find one of the addends when the

sum and its other addend are known. The subtraction symbol is written by “-” and

it is read “minus” or “subtract”.

5�

-4

-(+ 7)

+ 3

+ 10

-(+7) 3

Example :

9 – 5 is read 9 minus 5, and the difference is 4.

Examples :

1. 10 - 7 =

When we subtract a positive number, we move to the left on the number line

2. 3 – 7 =

When we subtract a positive number, we move to the left on the number line

3. I owe my brother Rp 5 thousand. I fold his pen, and he forgives Rp 3

thousand of my debt

I still owe my brother Rp 2 thousand

- 2

- (-3)

- 5

���� ����

��������

3 – 7 = ? -4

10 – 7 = ? 3

– 5 – (-3) = ? - 2

take away debt

If I subtract a positive number, I

move left. So to subtract a

negative number, I move right

6�

4. A diver dove 15 feet below sea level.

Then she swam down another 10 feet.

Where is she now?

The diver is 25 feet below sea level.�

c. Multiplication

Multiplication is form of repeated addition (Berston and Fisher, 1982).

The number that is multiplied is called multiplicand and the number that

multiplied by is called multiplier. The result of multiplication is called the product

(Berston and Fisher, 1982). The multiplication symbol is written by “x” or “�” or

“�” and it is read “multiply” or “times”. Pickover (2005:13) said that the

multiplication symbol “x” was introduced by The English mathematician William

Oughtred (1574-1660) in 1631 in his book Keys to Mathematics, published in

London.

Example :

4 x 6 is read 4 times 6, the product is 24.

Example :

1. 3 x 2 = 6

When multiplying integers, the first number tells how many sets there are.

The second number tells how many are in each set.

������������

����������

–1 5 – 10 = ? - 25 �

- 15

- (+10)

7�

2

2

2

6

2 2

6

2

3 x 2

When the first number is positive, multiplication can be thought of as repeated

addition. 3 x 2 means add three sets of two positive number. Adding three sets of

two positive number is six positive number in total. So three times two equals six.

2. 3 x (-2) = -6

3 x (-2) can be thought of as repeated addition, add three sets of two negative

number. Adding three sets of two negative number is six negative number in

total. So three times negative two equals negative six.

Two in each sets Three sets

8�

d. Division

Berston and Fisher (1982) said that division is a process of finding out

how many times one number is contained in another number. Furthermore, the

dividend or numerator is the number being divided; the number by which the

dividend is being divided is the divisor or denominator; the quotient is the result

of the division and shows the number of times the divisior goes into the dividend:

and the remainder is the amount remaining if the divisor does not go into the

dividend an even number of times (Berston and Fisher, 1982). The division

symbol is written by “÷” or “/” and it is read “divided by”. Division symbol “÷”

first appeared in print in Johann Heinrich Rahn’s Teutche Alegbra in 1659

(Pickover, 2005:20). Ashlock (1983:175) said that division is the inverse of

multiplication. Multiplication is used to find a product when its factors are known,

whereas division is used to find one of the factors when the product and its other

factor are known.

Example :

16 : 2 = 8 Result

Example :

1. 6 : 3 =

The result is 6 : 3 = 2

����������������������

���������������������

9�

2. – 6 : 3 =

The result is - 6 : 3 = - 2

3. 6 : (- 3) =

The result is 6 : (- 3) = - 2

4. – 6 : ( - 3) =

The result is - 6 : (- 3) = 2

2. The Properties of Number Operations

The following are the properties (also called prinsiples or laws) of number

operations which was written by Gibilisco (2004:20-21):

Additive Identity Element

When 0 is added to any real number a, the sum is always equal to a. The

number 0 is said to be the additive identity element:

a + 0 = a

10�

Additive Inverses

For every real number a, there exists a unique real number -a such that the

sum of the two is equal to 0. The numbers a and -a are called additive inverses:

a + (- a) = 0

Commutative Law For Addition

When any two real numbers are added together, it does not matter in which

order the sum is performed. The operation of addition is said to be commutative

over the set of real numbers. For all real numbers a and b, the following equation

is valid:

a + b = b + a

Associative Law For Addition

When adding any three real numbers, it does not matter how the addends are

grouped. The operation of addition is associative over the set of real numbers. For

all real numbers a1, a2, and a3, the following equation holds true:

(a1 + a2) + a3 = a1 + (a2+ a3)

Commutative Law For Multiplication

When any two real numbers are multiplied by each other, it does not matter in

which order the product is performed. The operation of multiplication, like

addition, is commutative over the set of real numbers. For all real numbers a and

b, the following equation is always true:

a x b = b x a

it also can be written without “times symbol” as:

ab = ba

11�

Associative Law For Multiplication

When multiplying any three real numbers, it does not matter how the

multiplicands are grouped. Multiplication, like addition, is associative over the set

of real numbers. For all real numbers a, b, and c, the following equation holds:

(ab)c = a(bc)

Multiplication Identity Element

When any real number a is multiplied by 1, the product is always equal to a. The

number 1 is said to be the multiplicative identity element:

a x 1 = a

Multiplication Inverses

For every nonzero real number a, there exists a unique real number �

� such that the

product of the two is equal to 1. The numbers a and �

� are called multiplicative

inverses:

�����

�� �

Furthermore, Gibilisco (2004:20) said “the multiplicative inverse of a real number

is also called its reciprocal”.

Distributive Law

For all real numbers a, b, and c, the following equation holds. The operation of

multiplication is distributive with respect to addition:

a(b + c) = ab + ac

The multiplication is also distributive with respect to subtraction:

a(b - c) = ab – ac

The distributive law can also be extended to division as long as there aren’t any

denominators that end up being equal to zero. For all real numbers a, b, and c,

where a � 0, the following equations are valid:

12�

�! " �#$

��

�!

�"

�#

�� ! " #

�! % �#$

��

�!

�%

�#

�� ! % #

The following is the order of operations:

1. Perform any calculations inside parentheses

2. Perform all multiplications and divisions, from left to right

3. Perform all addition and subtraction, from left to right

Examples:

1. 2 + 3 x 7 = 2 + 21 = 23

Reason:

2 + 3 x 7 means 2 + (7 + 7 + 7) = 2 + 21 = 23 (correct)

But, if we perform addition firstly:

2 + 3 x 7 = 5 x 7 = 35 (False)

2. 4 + 8 x (2 + 7) ÷ 12 – 7 = 4 + 8 x 9 ÷ 12 – 7

= 4 + 72 ÷ 12 – 7

= 4 + 6 – 7

= 10 – 7

= 3

3. The Bases of Number Ever Used

a. Roman Numeral System

The ancient Romans used letters of their alphabet to represent numbers,

and this method is still used in certain countries even today (Berston and

Fisher,1982). Originally the Roman numeral for five was a sketch of a

hand. Later this was simplified to a V. Observed that there is some use of

place value in Roman numerals IV and IX. The Roman system was based

on 10, since all their symbols for large numbers denote multiples of 10,

that is L = 5 x 10, C = 10 x10, etc. It is good experience to work some

&���'� ���������(�

����������

13�

arithmetic problems using these Roman numerals. Addition and

subtraction are relatively easy, but multiplication and division are not.

b. Babylonian Numeral System

Babylonian numeral system were written using a sexagesimal (base-

60) numeral system. From this derives the modern day usage of 60

seconds in a minute, 60 minutes in an hour, and 360 (60 x 6) degrees in a

circle, as well as the use of seconds and minutes of arc to denote fractions

of a degree. Babylonian advances in mathematics were facilitated by the

fact that 60 has many divisors. Also, unlike the Egyptians, Greeks, and

Romans, the Babylonians had a true place-value system, where digits

written in the left column represented larger values, much as in

the decimal system. They lacked, however, an equivalent of the decimal

point, and so the place value of a symbol often had to be inferred from

the context. On the other hand, this "defect" is equivalent to the modern-

day usage of floating point arithmetic; moreover, the use of base 60

means that any reciprocal of an integer which is a multiple of divisors of

60 necessarily has a finite expansion to the base 60. (In decimal

arithmetic, only reciprocals of multiples of 2 and 5 have finite decimal

expansions.) Accordingly, there is a strong argument that arithmetic Old

Babylonian style is considerably more sophisticated than that of current

usage.

c. Greece Numeral System

Greece numeral system was based on 10 but had neither place value nor a

symbol for zero. They used the letters of their alphabet for numbers, but

you need not know the Greek alphabet in order to understand the system.

The numerals and some of their names were as followers.

d. Hindu-Arabic Numeral System

The number system most universally used today is known as the decimal

system. It probably originated in India and was brought to Europe by the

Arabs. The digits 1, 2, 3, ... and 0 are called Hindu-Arabic numerals. It is

a system based upon tens, and the starting point is indicated by a dot

14�

known as the decimal point. Whole numbers are written to the left of the

decimal point and increase by tens depending on the position of the

numerals. Numbers to the right of the decimal point indicate amounts

less than the number 1 and are also in groups of ten.

4. The History of Months

The history of months and their names begun in Rome. The original Roman

year had 10 named months Martius "March", Aprilis "April", Maius "May",

Junius "June", Quintilis "July", Sextilis "August", September "September",

October "October", November "November", December "December", and

probably two unnamed months in the dead of winter when not much

happened in agriculture. The year began with Martius "March". Numa

Pompilius, the second king of Rome circa 700 BC, added the two months

Januarius "January" and Februarius "February". He also moved the beginning

of the year from Marius to Januarius and changed the number of days in

several months to be odd, a lucky number. After Februarius there was

occasionally an additional month of Intercalaris "intercalendar". This is the

origin of the leap-year day being in February. In 46 BC, Julius Caesar

reformed the Roman calendar (hence the Julian calendar) changing the

number of days in many months and removing Intercalaris.

a. Calendar of Romulus

Roman writers attributed the original Roman calendar to Romulus, the

mythical founder of Rome around 753 BC. The Romulus calendar had

ten months with the spring equinox in the first month:

Calendar of Romulus

Martius (31 days)

Aprilis (30 days)

Maius (31 days)

Iunius (30 days)

Quintilis [2]

(31 days)

Sextilis (30 days)

September (30 days)

15�

October (31 days)

November (30 days)

December (30 days)

The regular calendar year consisted of 304 days, with the winter days

after the end of December and before the beginning of the following

March not being assigned to any month.

The names of the first four months were named in honour of Roman

gods: Martius in honour of Mars; Aprilis in honour of Fortuna Virilis

(later Venus Verticordia in the mid-4th century AD); Maius in honour of

Maia; and Iunius in honour of Juno. The names of the months from the

fifth month on were based on their position in the calendar: Quintilis

comes from Latin quinque meaning five; Sextilis from sex meaning six;

September from septem meaning seven; October from octo meaning

eight; November from novem meaning nine; and December from decem

meaning ten.

b. Calendar of Numa

Numa Pompilius, the second of the seven traditional kings of Rome,

reformed the calendar of Romulus around 713 BC. The Romans

considered odd number to be lucky, so Numa took one day from each of

the six months with 30 days, reducing the number of days in the 10

previously defined months by a total of six days.

There were 51 previously unallocated winter days, to which were added

the six days from the reductions in the days in the months, making a total

of 57 days. These he made into two months, January and February, which

he prefixed to the previous 10 months. January was given 29 days, while

February had the unlucky number of 28 days, suitable for the month of

purification. This made a regular year (of 12 lunar months) 355 days long

in place of the previous 304 days of the Romulus calendar. Of the 11

16�

months with an odd number of days, four had 31 days each and seven

had 29 days each:

Civil calendar Religious calendar

According to

Macrobius

and Plutarch

According to Ovid

(modern order due to

Decemviri, 450 BC)

According to Fowler

Ianuarius (29) Ianuarius Martius

Februarius (28) Martius Aprilis

Martius (31) Aprilis Maius

Aprilis (29) Maius Iunius

Maius (31) Iunius Quintilis

Iunius (29) Quintilis Sextilis

Quintilis (31) Sextilis September

Sextilis (29) September October

September (29) October November

October (31) November December

November (29) December Ianuarius

December (29) Februarius Februarius

February consisted of two parts, each with an odd number of days. The

first part ended with the Terminalia on the 23rd, which was considered

the end of the religious year, and the five remaining days formed the

second part.

c. Julian Calender

The Julian calendar, introduced by Julius Caesar in 46 BC (708 AUC),

was a reform of the Roman calendar. It took effect in 45 BC (709 AUC),

shortly after the Roman conquest of Egypt. It was the predominant

calendar in the Roman world, most of Europe, and in European

settlements in the Americas and elsewhere, until it was refined and

superseded by the Gregorian calendar. The difference in the average

length of the year between Julian (365.25 days) and Gregorian (365.2425

days) is 0.002%.

17�

The Julian calendar has a regular year of 365 days divided into 12

months, as listed in Table of months. A leap day is added to February

every four years. The Julian year is, therefore, on average 365.25 days

long. It was intended to approximate the tropical (solar) year. Although

Greek astronomers had known, at least since Hipparchus, a century

before the Julian reform, that the tropical year was a few minutes shorter

than 365.25 days, the calendar did not compensate for this difference. As

a result, the calendar year gained about three days every four centuries

compared to observed equinox times and the seasons. This discrepancy

was corrected by the Gregorian reform of 1582. The Gregorian calendar

has the same months and month lengths as the Julian calendar, but inserts

leap days according to a different rule. Consequently, the Julian calendar

is currently 13 days behind the Gregorian calendar; for instance, 1

January in the Julian calendar is 14 January in the Gregorian. Old Style

(O.S.) and New Style (N.S.) are sometimes used with dates to indicate

either whether the start of the Julian year has been adjusted to start on 1

January (N.S.) even though documents written at the time use a different

start of year (O.S.), or whether a date conforms to the Julian calendar

(O.S.) rather than the Gregorian (N.S.). Dual dating uses two consecutive

years because of differences in the starting date of the year, or includes

both the Julian and Gregorian dates.

The Julian calendar has been replaced as the civil calendar by the

Gregorian calendar in almost all countries which formerly used it,

although it continued to be the civil calendar of some countries into the

20th century. Most Christian denominations in the West and areas

evangelized by Western churches have also replaced the Julian calendar

with the Gregorian as the basis for their liturgical calendars. However,

most branches of the Eastern Orthodox Church still use the Julian

calendar for calculating the dates of moveable feasts, including Easter

(Pascha). Some Orthodox churches have adopted the Revised Julian

18�

calendar for the observance of fixed feasts, while other Orthodox

churches retain the Julian calendar for all purposes. The Julian calendar

is still used by the Berber people of North Africa, and on Mount Athos.

In the form of the Alexandrian calendar, it is the basis for the Ethiopian

calendar, which is the civil calendar of Ethiopia.

19�

CHAPTER 3

CONCLUSION AND SUGGESTION

1. Conclusion

a. There are 4 (four) number operations: addition, subtraction, multiplication,

and division. Addition is the process of combining two or more numbers and

arriving at a single total. Subtraction is the process of finding the difference

between two amounts. Division is the process of splitting into equal parts.

Multiplication is form of repeated addition.

b. The properties of number operations consist of idendity element, inverses,

commutative, assosiative, and distributive laws.

c. The Bases Number Ever Used are Roman Numeral System, Babylonian

Numeral System, Greece Numearl System, Hindu-Arabic Numeral System.

d. The History of Months and their names begun in Rome. The original Roman

year had 10 named months Martius "March", Aprilis "April", Maius "May",

Junius "June", Quintilis "July", Sextilis "August", September "September",

October "October", November "November", December "December". Numa

Pompilius, the second king of Rome circa 700 BC, added the two months

Januarius "January" and Februarius "February"

2. Suggestion

We suggest to all readers in order to master these number operations

because so necessary to be understood as basic knowledge. Especially for the

teachers who teach mathematics in english, we hope this paper become one of

references which is used.

20�

REFERENCES

Brumfiel,Charles F., Dkk. 1962. Fundamental Concepts of Element Mathematics.

USA : Addison-Wesley Publising Copany,INC

Pickover, Clifford A. (2005). A Passion for Mathematics : Numbers, Puzzles,

Madnes, Religion, and The Quest for Reality. USA: John Wiley & Sons,

Inc., Hoboken, New Jersey.

Gibilisco, Stan. (2004). Everyday Math. USA: The McGraw-Hill Companies, Inc.

Berston & Fisher. (1982). Collegiate Business Mathematics. Collegiate Business

Mathematics.

Ashlock, et. al. (1983). Guiding Each Child’s Learning of Mathematics: A

Diagnostic Approach to Instruction. USA: Bell & Howell Company.

Donna & Lawrence. (1980). Mathematics for Consumers with Business

Applications. Philippines: Addison-Wesley Publishing Company, Inc.

http://en.wikipedia.org/wiki/Arithmetic.htm. (online, diakses tanggal 10

September 2014)

http://en.wikipedia.org/wiki/History_of_mathematics (online, diakses tanggal 25

September 2014)

http://en.wikipedia.org/wiki/Julian_calendar (online, diakses tanggal 25

September 2014)

http://en.wikipedia.org/wiki/Roman_calendar (online, diakses tanggal 25

September 2014)