# JS1 Mathematics week 7

Subject:- MATHEMATICS
Class:- JSS 1
References: – MF Macrae et al 2007. New General Mathematics for Junior Secondary Schools 1 pgs 140 – 151
J. S Oluwasanmi 2014. Essential Mathematics for Junior Secondary Schools 1 pgs 253 – 264
Week: 7
Topic:- Statistics 1: Purpose of data collection and Presentation of data
Subtopic: – Statistics, data and presentation
Content
Statistics is the branch of mathematics which deals with the study of data. Data mean information which are usually given in the form of numbers or facts. The information is called Statistical data or Statistics. Statistics involves:
Collecting data: to distinct ways of collection data are by carrying out experiments and by survey.
sorting and tabulating data
presenting data visually by means of diagrams
interpreting result
Types of Presentation
list and table
graphs
Lists and tables
Rank order: means in order from highest to lowest
Frequency table: means the number of times something happens.
Tally: tally chart are usually grouped in fives. Four tallies are drawn vertically with the fifth one drawn across them 1111
Graphical presentation
Pictogram: uses picture or drawing to give a quick and easy meaning to statistical data.
Bar chart: is very like pictogram. Data are represented by a bar instead of a picture. The height represent the frequency of each value.
Pie chart: A pie chart is a graph in the shape of a circular pie.
Examples
The following raw data shows the number of vehicle owned by 25 business men in Lagos. 2, 5, 3, 4, 6, 3, 4, 7, 5, 4, 7, 7, 8, 9, 5, 3, 4, 5, 7, 4, 4, 8, 2, 2, 5.
Arrange the data in increasing order
Arrange the data in decreasing order
How many men own 3 vehicles, 4 vehicles, 9 vehicles and less than 5 vehicles each?
Solution
Increasing order: 2, 2, 2, 3, 3, 3, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 6, 7, 7, 7, 7, 8, 8, 9.
Creasing order: De9, 8, 8, 7, 7, 7, 7, 6, 5, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 3, 3, 3, 2, 2, 2.
3 men own 3 vehicles, 6 men own 4 vehicles, 1 man own 9 vehicles and 12 men own less than 5 vehicles each.
The following figures show the number of children per family in a sample of 40 households. 1, 2, 4, 3, 5, 3, 8, 3, 2, 2, 3, 4, 5, 6, 5, 4, 2, 1, 3, 2, 4, 5, 3, 8, 7, 6, 5, 4, 5, 7, 6, 3, 8, 6, 3, 5, 7, 5, 4, 3.
Use a tally mark to prepare a frequency table for this data
What is the highest frequency of numbers of children per family?
Solution
Frequency table
No of children per familyTallyFrequency1ll22llll53llll llll94llll l65llll lll86llll47lll38lll3Total 40
9 households has 3 children each. The highest frequency of number of children per family is 3.
A student was given ₦600 in June as a pocket money. He spent the money as follows
Food = ₦200
Transport = ₦100
Books = ₦120
Rent = ₦150
Miscellaneous = ₦30
Draw a pie chart and bar chart to illustrate the data
Solution
There are 3600 in a full circle and the total amount spent was ₦600
₦1 represent by 3600
600 = 0.60 or multiply the fraction by 3600
ItemsAmount spent in ₦Angle
Method 1Angle
Method 2Food200200 x 0.6 = 1200200/600 x 3600 = 1200Transport100100 x 0.6 = 600100/600 x 3600 = 600Books120120 x 0.6 = 720120/600 x 3600 = 720Rent150150 x 0.6 = 900150/600 x 3600 = 900Miscellaneous3030 x 0.6 = 18030/600 x 3600 = 180 Total 60036003600

Assignment
Ex 18b question 1 and 3