Circle Graph Completion 52Dfae
1. Problem: Complete the charts by finding missing percents or angles, ensuring percents total 100% and angles total 360° for each survey.
2. Formula: Use the relationship between percent and angle in a circle graph:
$$\text{Angle} = \frac{\text{Percent}}{100} \times 360^\circ$$
or equivalently,
$$\text{Percent} = \frac{\text{Angle}}{360^\circ} \times 100$$
3. Part a) Daily newspaper habit:
- Given: Delivered to home = 40%, Never look at = 10%, Buy occasionally angle = 180°
- Find percent for buy occasionally:
$$\text{Percent} = \frac{180}{360} \times 100 = 50\%$$
- Check percents sum: 40% + 50% + 10% = 100%
- Find angle for delivered to home:
$$\text{Angle} = \frac{40}{100} \times 360 = 144^\circ$$
- Find angle for never look at:
$$\text{Angle} = \frac{10}{100} \times 360 = 36^\circ$$
4. Part b) How students spend money:
- Given: Clothes and personal care = 30%, Savings = 15%, Entertainment angle = 162°, Snacks angle = 36°
- Find percent for entertainment:
$$\text{Percent} = \frac{162}{360} \times 100 = 45\%$$
- Find percent for snacks:
$$\text{Percent} = \frac{36}{360} \times 100 = 10\%$$
- Check percents sum: 45% + 30% + 10% + 15% = 100%
- Find angle for clothes and personal care:
$$\text{Angle} = \frac{30}{100} \times 360 = 108^\circ$$
- Find angle for savings:
$$\text{Angle} = \frac{15}{100} \times 360 = 54^\circ$$
5. Part c) Favourite kind of pie:
- Given: Apple = 20%, Blueberry angle = 54°, Other = 55%
- Find percent for blueberry:
$$\text{Percent} = \frac{54}{360} \times 100 = 15\%$$
- Sum known percents: 20% + 15% + 55% = 90%
- Find percent for cherry:
$$100\% - 90\% = 10\%$$
- Find angle for cherry:
$$\text{Angle} = \frac{10}{100} \times 360 = 36^\circ$$
Final answers:
a) Buy occasionally: 50%, Delivered to home angle: 144°, Never look at angle: 36°
b) Entertainment: 45%, Clothes and personal care angle: 108°, Snacks: 10%, Savings angle: 54°
c) Blueberry: 15%, Cherry: 10%, Cherry angle: 36°
Each circle graph can be drawn by marking these angles as segments of a 360° circle with labels for clarity.