The image shows the cover of a
Grade 7 Mathematics Learner's Book titled *"PlusOne Mathematics"*, authored by Passmore Moyo. The cover features a student drawing a
pie chart on a chalkboard, illustrating a math problem related to percentages.
Task on the Chalkboard:
The task written on the board is:
>
1. Draw a pie chart for the following:
> - a) Beans – 10%
> - b) Maize – 50%
> - c) Tobacco – 40%
This is a
data representation problem where students are asked to create a
pie chart based on given percentages.
---
✔ Let’s Solve the Problem Step-by-Step:
A
pie chart represents data as slices of a circle, where each slice's angle corresponds to the percentage of the whole (360°).
#### Step 1: Understand the Percentages
We have three categories:
- Beans: 10%
- Maize: 50%
- Tobacco: 40%
Check total:
10% + 50% + 40% =
100% → Good! This adds up correctly.
#### Step 2: Convert Percentages to Angles
Since a full circle has
360 degrees, we calculate each sector’s angle:
-
Beans:
\( 10\% \times 360^\circ = 0.10 \times 360 = 36^\circ \)
-
Maize:
\( 50\% \times 360^\circ = 0.50 \times 360 = 180^\circ \)
-
Tobacco:
\( 40\% \times 360^\circ = 0.40 \times 360 = 144^\circ \)
#### Step 3: Draw the Pie Chart
To draw the pie chart:
1. Draw a circle.
2. Use a protractor to measure and mark angles starting from a fixed point (e.g., the top or right).
- Start with
Maize (180°) — this is half the circle, so it’s a straight line across.
- Then add
Tobacco (144°) in one direction.
- Finally,
Beans (36°) will fill the remaining space.
#### Step 4: Label Each Sector
Label each slice with:
- The category name (Beans, Maize, Tobacco)
- The percentage
---
📌 Summary of the Solution:
| Category | Percentage | Angle in Degrees |
|-----------|------------|------------------|
| Beans | 10% | 36° |
| Maize | 50% | 180° |
| Tobacco | 40% | 144° |
✔ The pie chart should show:
- A
half-circle (180°) for Maize,
- A
large quarter-like section (144°) for Tobacco,
- A
small slice (36°) for Beans.
---
💡 Why This Matters:
Pie charts help visualize how parts make up a whole. In real life, they’re used in budgets, surveys, agriculture (like crop distribution), and more.
This exercise helps Grade 7 learners understand:
- How to convert percentages into angles
- How to use a protractor
- Data representation skills
Let me know if you'd like a visual sketch or printable version of this pie chart!
Parent Tip: Review the logic above to help your child master the concept of 7th grade text books.
