Data handling and probability and exam preparation (Grade 6) – Week 8 focus
Download the Lessonotes Mobile South Africa app for faster lesson access on Android and iPhone.
Subject: Mathematics
Class: Grade 6
Term: Term 4
Week: 8
Theme: General lesson support
This page supports the lesson note with a companion video and a short classroom-ready summary.
For class groups and homework, share this lesson page so learners also get the summary, objectives, and full lesson context.
Data handling and probability are essential skills that help us understand and interpret the world around us. In South Africa, these skills are crucial for understanding statistics related to population growth, crime rates, economic indicators, and even predicting weather patterns for agriculture. This week, we'll be focusing on reviewing key data handling concepts and introducing basic probability, all while preparing for upcoming assessments. This week acts as a consolidation week where we revise key concepts covered in previous weeks and reinforce learners skills through exam-style questions.
2.1 Data Collection and Organisation Data is information. We collect data by asking questions (surveys), observing, or conducting experiments. A tally chart is a way to record data as it is collected. A frequency table summarises the data by showing how often each piece of information occurs.
Example: Imagine we want to know the favourite fruits of Grade 6 learners in a class. We conduct a survey. | Fruit | Tally Marks | Frequency | | ------- | ----------- | --------- | | Apple | |||| || | 7 | | Banana | |||| | | 6 | | Orange | |||| |||| | 9 | | Mango | |||| | 4 | | Grapes | |||| | || | 7 | 2.2 Data Representation We can represent data using different types of graphs: Bar Graph: Uses bars of different lengths to show the frequency of each category.
Pie Chart: Uses sectors of a circle to show the proportion of each category. The whole circle represents 100% of the data.
Pictograph: Uses pictures to represent the data. Each picture represents a specific quantity.
Bar Graph Example (using the fruit data): A bar graph of the fruit data will have fruit names on the horizontal axis and frequency on the vertical axis. The height of each bar corresponds to the frequency of that fruit.
Pie Chart Example (using the fruit data): To create a pie chart, we need to calculate the percentage of learners who prefer each fruit. The total number of learners who responded is 7 + 6 + 9 + 4 + 7 =
3
3. Apple: (7/33) 100% = 21.2% Banana: (6/33) 100% = 18.2% Orange: (9/33) 100% = 27.3% Mango: (4/33) 100% = 12.1% Grapes: (7/33) 100% = 21.2% A pie chart will then have sectors representing these percentages for each fruit.
Pictograph Example (using the fruit data): Let's say one picture of a fruit represents 2 learners.
Apple: 3 ½ fruit pictures Banana: 3 fruit pictures Orange: 4 ½ fruit pictures Mango: 2 fruit pictures Grapes: 3 ½ fruit pictures 2.3 Data Interpretation Interpreting data means drawing conclusions from the information presented in graphs and tables. We can compare different categories, identify trends, and make predictions.
Example: Looking at the fruit data: Which fruit is the most popular? Orange (highest frequency) Which fruit is the least popular? Mango (lowest frequency) How many learners prefer apples or grapes? 7 + 7 = 14 learners 2.4 Probability Basics Probability is the chance of something happening.
We use words like: Certain: It will definitely happen.
Likely: It has a good chance of happening.
Unlikely: It probably won't happen.
Impossible: It cannot happen.
Example: The sun will rise tomorrow: Certain.
You will win the Lotto jackpot this week: Unlikely.
It will snow in Durban in July: Impossible (very, very unlikely). Probability can be expressed as a fraction: Probability = (Number of favorable outcomes) / (Total number of possible outcomes)
Example: A bag contains 5 red balls and 3 blue balls. What is the probability of picking a red ball? Probability (red ball) = 5 / (5+3) = 5/8 2.5 Exam Preparation: Focus on understanding the questions, identifying the key information needed, and choosing the correct methods to solve the problem. Practice answering questions under timed conditions to improve speed and accuracy. Review past exam papers and focus on identifying areas where you need more practice. Guided Practice (With Solutions)
Question 1: A survey was conducted to find out the favourite sports of Grade 6 learners.
The results are shown below: | Sport | Frequency | | -------- | --------- | | Soccer | 15 | | Netball | 10 | | Rugby | 8 | | Cricket | 7 | Draw a bar graph to represent this data.
Solution: Draw the axes. Label the horizontal axis "Sport" and the vertical axis "Frequency". Choose a suitable scale for the vertical axis. In this case, a scale of 0 to 16, increasing in units of 2, is appropriate. Draw bars for each sport with heights corresponding to their frequencies. Label each bar and the graph.
Commentary: This question tests the ability to represent data using a bar graph. Make sure the axes are correctly labelled and the scale is appropriate.
Question 2: A bag contains 12 marbles: 4 are green, 3 are blue, and 5 are red. What is the probability of picking a blue marble from the bag?
Solution: Identify the number of favorable outcomes: 3 (blue marbles) Identify the total number of possible outcomes: 12 (total marbles)
Calculate the probability: Probability (blue marble) = 3/12 = 1/4
Commentary: This question tests the understanding of basic probability. Remember to simplify the fraction if possible.
Question 3: The following data shows the number of rainy days in each month of the year in Cape Town: January: 2 days, February: 3 days, March: 5 days, April: 8 days, May: 12 days, June: 15 days, July: 16 days, August: 14 days, September: 10 days, October: 7 days, November: 4 days, December: 2 days. What is the month with the most rainy days? What is the month with the least rainy days?