Statistics Basic 6 Mathematics Lesson Note

Data Representation

Data can be shown in different ways to make it easier to understand.

Pictogram

Uses pictures or symbols to show data. Each symbol represents a certain number.

Bar Chart

Uses bars of different heights to show data. The height shows the quantity.

Pie Chart

Uses a circle divided into sections to show parts of a whole.

Measures of Central Tendency

Mode

The number that appears most often in a set of data. 

Example: In 2, 3, 5, 3, 7, 3, 9 – the mode is 3

Median

The middle number when data is arranged in order. 

Example: In 2, 4, 6, 8, 10 – the median is 6

Mean (Average)

Add all numbers and divide by how many numbers there are. 

Example: Mean of 4, 6, 8 = (4+6+8) ÷ 3 = 18 ÷ 3 = 6

Range

The difference between the highest and lowest values. 

Example: In 3, 7, 2, 9, 5 – Range = 9 – 2 = 7

Probability

Probability tells us how likely something is to happen.

• Certain = will definitely happen
• Likely = probably will happen
• Unlikely = probably won’t happen
• Impossible = will never happen

EXERCISES

1. Find the mode:

1. 5, 8, 3, 5, 9, 5, 2. Mode = _______
2. 12, 15, 12, 18, 12, 20. Mode = _______
3. Red, Blue, Red, Green, Red, Yellow. Mode = _______

1. Find the median:

1. 3, 7, 5, 9, 1. Median = _______
2. 10, 14, 12, 16, 18, 8. Median = _______
3. 25, 30, 20, 35, 15. Median = _______

1. Find the mean:

1. 6, 8, 10, 12. Mean = _______
2. 15, 20, 25, 30, 35. Mean = _______
3. 4, 7, 5, 8, 6. Mean = _______

1. Find the range:

1. 12, 8, 15, 3, 11. Range = _______
2. 25, 18, 30, 22, 35. Range = _______
3. 45, 38, 52, 41, 49. Range = _______

1. Data Interpretation: The table shows favorite subjects of 30 students:

1. Which subject is most popular? _______
2. How many more students like Maths than Science? _______
3. What fraction of students like English? _______

1. Probability: A bag contains 5 red balls, 3 blue balls, and 2 green balls.

1. What color ball are you most likely to pick? _______
2. What color ball are you least likely to pick? _______
3. Is it likely or unlikely to pick a blue ball? _______

1. Real Life Problems:

1. Adunni scored these marks in 5 tests: 85, 90, 78, 90, 82.
   1. Mode = _______
   2. Median = _______
   3. Mean = _______
2. The heights of 7 students (in cm) are: 140, 135, 142, 138, 135, 145, 140
   1. Mode = _______
   2. Range = _______
3. In a class survey, 15 students like football, 10 like basketball, 8 like tennis, 7 like swimming. Draw a simple bar chart.

1. Pictogram Reading: 🍎🍎🍎 = 6 apples sold 🍌🍌 = 4 bananas sold
   🥭🥭🥭🥭 = 8 mangoes sold

1. How many fruits were sold in total? _______
2. Which fruit sold the most? _______
3. How many more mangoes than bananas were sold? _______

Answers: 

A: 1.5 2.12 3.Red 

B: 1.5 2.13 3.25 

C: 1.9 2.25 3.6 

D: 1.12 2.17 3.14 

E: 1.Maths 2.6 3.8/30 or 4/15 

F: 1.Red 2.Green 3.Unlikely 

G: 1.Mode=90, Median=85, Mean=85 2.Mode=135&140, Range=10 H: 1.18 2.Mangoes 3.4