GLORY TWINKLE IX E

Anggun Nugraha OktavianiDeti Nur KarinaFiona SalfadillaRifda Nadifah

Umroh Indah Lestari

Hallo ....We are GLORY TWINKLE from Nedusi IX

E

We will present our project about STATISTICS

Let’s check it out !

STATISTICS

A. The Definition Of Statistic

• Statistics is a study or scientific method of collecting, organizing, processing, presenting, analizyng data and drawing a conclusion according to the result of the data analysis.

From the following definition, we know that statistics is closely releated to data.

• Data is the information obtained from the result of observation or research .

• The singular form of data is datum• Data can describe a situation, so that

based on the data we can draw a conclution

1) Presenting Data

According to the types, data can be divided into two. They are :

1. Qualitative dataare data releated to the category or characteristic of an object.For examples :a. Data about the cleanest country in the world (Singapore, Japan, Australia, or the other)b. Data about the best female singer (BoA, Taylor Swift, Beyonce, Rihanna, Whitney Housten or the other)

Qualitative data are usually obtained by interview

2. Quantitative data, are obtained from the result of numerical recording (in the form of numbers)For examples are :a. Data about the weight in the class

(48kg, 45.5kg, 45kg, 49kg, 48kg, 50kg and so on)b. Data about the number of sister (2, 3, 2, 4, 1, 0 and so on)

As we know, the data are used to draw a conclusion. But before draw a conclusion, the data that have been collected beforehand arranged, processed, presented, then analyzed carefully, accurately and according to the righttheory.

There are several examples of conclutions :a. The average of students in the class IX E is 14

years oldb. The favorite teacher in Nedusi is Mr. Yokoc. The favorite subject in class IX E is Mathematic

Based on the data that have been analyzed, we can draw a conclusion

2). Collection of Data

• Collection of data is the beginning stage (the first step) in the statistical activity.

• Collecting data can be performed by interview of questionnaire, then continued by one of the following activities :

a. Countingb. Measuringc. Recording data by tallies

• Simple data is only consist of relatively small data.

• It isn’t necessary to group them, ordering data is enaugh

• In general, the collected statiscal data are still scattered and the measurement isn’t in order.

• However, to simply presentation and processing of data, we need to order them from the lowest value to the highest value. After the data are ordered, we can determine the highest and the lowest value of data.

3). Ordering Single Data

Measures Of Central Tendency

• The collected and even the ordered data don’t automatically give clear information.

• To get clearer information, we need measures to represent the collection of data.

• The measures are known as the measures of central tendency

• By knowing measures of central tendency, we can find out the value of the centralized data.

The Measures Of Central Tendency Consist Of 3 Measures,

Namely :

1. MEAN (arithmetic mean) 2. MODE (the value that occurs most

often)3. MEDIAN (the middle value)

1. Mean• In statistic, the average value is usually called

arithmetic mean or simply mean.• So, mean is the average value of all data values• Mean is one of the measures of central tendency

that is most often used.• The mean of data set is the sum of all data values

divided by the number of data.

☞Example : Data = 7 8 9 8 5 9 9 6 4

The ordered data =4 5 6 7 8 8 9 9 9

= 7.3

n

XX

Mean = ¿𝟕𝟑𝟏𝟎

𝐌𝐞𝐚𝐧=𝐓𝐡𝐞𝐬𝐮𝐦𝐨𝐟 𝐚𝐥𝐥 𝐯𝐚𝐥𝐮𝐞𝐬𝐓𝐡𝐞𝐧𝐮𝐦𝐛𝐞𝐫 𝐨𝐟 𝐝𝐚𝐭𝐚

2. Mode• Mode is generally used to express the tendency

which most frequently happens.• In statistics, the mode means the value that

occurs most frequently or the value of highest frequency.

Example :

Data = 3 5 8 6 5 9 8 8 6

The ordered data = 3 5 5 6 6 8 8 8 8 9

Based on the data above, the value of highest frequency is 8

No. Marks TallyFrequen

cy

1. 3 l 1

2. 5 ll 2

3. 6 ll 2

4. 8 llll 4

5. 9 l 1So, the mode is 8

3. Median• Median is a measure of central tendency used to analyze data.• If the number of data ordered is odd, then the median is the

data value right in the middle that divides the data into two equal parts

• And if the number of data ordered is even, then the median is the mean of two data values in the middle

Median = The middle value after being ordered

Data : 9 9 7 5 8 7 3 6 4 The ordered data : 3 4 5 6 7 7 8 9 9

Median = 3 4 5 6 7 7 8 9 9 4 4Median

So, the median is 7

a. If n is odd, then the median is

b. If n is even, then the median is

Example :

Because n is odd (9), so the median is in the order to : = = 5

C. The Presentation Of Data

• The data collected and ordered according to the need should be presented in a certain form in such away that they can be read and interpreted easily

The presentation of statiscal data can be performed in two methods, they are :

1. Presented in the form of list or table a. Frequency table of single data b. Frequency table of grouped data

2. Presented in the form of a diagram or graph a. Pictogram (A method of presenting information using picture) b. Bar chart (A method of presenting data in bars) c. Line graph (A method of presenting data in a line) d. Pie charts (A method of presenting data in a circular region)

A. Pictogram

B. Bar Chart

C. Line Graph

D. Pie Charts

Quartile

• Quartile means the grouping of four, split the data that has been sorted into four equal parts.

• To present quartile, we used Q symbol.Q₁ = initial quartile / bottom quartile (¼)

Q₂ = middle quartile / median (¾)

Q₃ = upper quartile (²⁄₄)

We Have Some Observation In Class VII C And Class VII G

Curious ?Do you want to know ?

Serious ? Okay Let’s check it out !

Observation In Class VII G

Questions :1. How many sister

do you have?2. How many

brother do you have?

3. When you were in class six, what rank did you get ?

(Quantitative Data)

1. The Number of Sisters Owned by Students of VII G

Haven't Sister

Have 1 Sister

Have 2 Sisters

Have 3 Sisters

Have 4 Sisters

Have 5 Sisters

0

2

4

6

8

10

12

Sisters

Sisters

Stu

den

ts

So, from the data we can make a conclution :

a. The students that haven’t sister are 10 studentsb. The students that have 1 sister are 8 studentsc. The students that have 2 sisters are 6 studentsd. The students that have 3 sisters are 2 studentse. The student that have 4 sisters is nothingf. The students that have 5 sisters are 2 students

The number of students that have the most sister are 2 studentsAnd the students that haven’t sister are 4 students

2. The Number of Brothers Owned by Students of VII G

10

9

3

6

Broters

Students That Haven't BrotherStudents That Have 1 BrotherStudents That Have 2 BrothersStudents That Have 3 Brothers

So, from the data we can make the conclution :

a. The students that haven’t brother 10 studentsb. The students that have 1 brother are 9 studentsc. The students that have 2 brothers are 3 studentsd. The students that have 3 brothers are 6 studentse. The student that have 4 brothers and 5 brothers is nothing

The number of students that have the most brothers (3 brothers) are 6 studentsAnd the number of students that haven’t brother are 10 students

3. The Rank Of Students VII G When

They Were In Class Six

Ranked Students

1

2

3

4

5

8

9

10

11

12

13

14

18

19

20

4. The Interest or The Favorite Language in Grade VII C

Bahasa Indonesia

English

Japan

France

Bahasa Indramayu

0 2 4 6 8 10 12 14

Favorite Language

Favorite Language

Observation In Class VII C

Question :1. What kind of

language do you like ?

2. Which country will be visited most ?

3. Which city will you go to your study tour ?

(Qualitative Data)

So, From The Data We Can Make Conclution :

a. The students who interested in Bahasa Indonesia are 3 students

b. The students who interested in English are 14 students

c. The students who interested in Japan Language are 9 students

d. The students who interested in France are 2 students

e. The student who interested in Indramayu Language is nothing

So, English is the most interested language. And Indramayu language isn’t interested with all students VII C

5. The Country Will Be Visited Most By Students VII C

41%

17%24%

7% 3% 3%3%

The Countries

South Korea

Japan

France

Saudi Arabia

Holand

Rumania

AustraliaThe number of students VII C is 28 students

So, from the data we can make the conclution :

o The number of students VII C will be visited South Korea are 12 studentso The number of students VII C will be visited Japan are 5 studentso The number of students VII C will be visited France are 7 studentso The number of students VII C will be visited Saudi Arabia are 2 studentso The number of students VII C will be visited Holand is 1 studento The number of students VII C will be visited Rumania is 1 studento The number of students VII C will be visited Australia is 1 student

So, the city will be visited most is South KoreaAnd the city will be visited least is Holland, Rumania, and Australia

6. The City That Very Want To Visit To Your Study tour

0 1 2 3 4 5 6 7 80

2

4

6

8

10

12

Cities

Fre

qu

en

cy

So, from the data we can make the conclusion

• The students who choose Bali to visit to their study tour are 11 students• The students who choose Lombok to visit to their study tour are 5 students• The students who choose Yogyakarta to visit to their study tour are 2

students• The students who choose Paris to visit to their study tour are 5 students• The student who choose Jakarta to visit to their study tour is nothing• The student who choose Bandung to visit to their study tour is nothing• The student who choose Rajaampat to visit to their study tour is 1 student

So, the city that most choose to visit to students of VII C’s study tour is South KoreaAnd the cities that not choose to visit to students of VII C’s study tour are Jakarta and Bandung

We Have Learnt About Statistics

So, let’s try to answer these exercises

EXERCISE

1. Given the following data2 6 8 1 4 3 5 3 9 46 8 4 2 5 5 2 5 5 54 8 7 7 6 9 4 6 7 5Based on the data above :a. Make the frequency tableb. Find the mean, the mode and the median

2. The mean mark of mathematics test of 15 students is 8.6 if Sofhie’s mark is included, then the mean mark becomes 8.7 find Dinda’s mark in the test.

3. The mean weight of a group of children is 38 kg. Children having a mean weight of 40 kg are added, then the mean weight becomes 38.4 kg. Find the number of children at first

4. Consider the table belowKINDS OF PEOPLE’S

OCCUPATIONS IN VILLAGE A

NO. Kinds Of Occupations Frequency

1 Public Servants 56

2 Private Employees 42

3 Farmers 84

4 Traders 126

5 Workers 28

The frequency table above shows the data about the kinds of occupations of people at a village. Make a pie chart based on the data.

5. The number of classes and the class interval in the table of frequency distribution respectively are ...

Value Frequency

30-34 2

35-39 7

40-44 11

45-49 4

50-54 3

Good Luck !

PRESENTED BY :ANGGUN NUGRAHA OKTAVIANI

DETI NUR KARINAFIONA SALFADILLA

RIFDA NADIFAHUMROH INDAH LESTARI

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http://www.deepyudha.blogspot.com/

THANKS FOR WATCHING OUR PRESENTATION