🥧 PIE CHART INSTRUCTIONS:

1) In your Science Notebook take notes on Pie Charts.
2) After taking notes, complete Practice CAST Question below.
3) Then click Continue to complete the next section of notes.
4) Turn In: I will be stamping completed notes!

Pie Charts – Parts of a Whole

Pie Charts

Pie charts show parts of a whole as percentages. In chemistry and biochemistry, they can show composition, like what is in a food or a cell.

Parts of a Whole

Snack Bar Composition

Question: "What percent of this snack bar is carbohydrates, protein, fat, and water?"

Component	Percentage (%)
Carbohydrates	40
Protein	15
Fat	15
Water	30

Which substance makes up the largest proportion? (Look for the biggest slice.)
What percentage is carbohydrates? (Read the label or the legend.)
Which component is the smallest slice?

Always check that all pieces add up close to 100%.

Pie Chart: Snack Bar Composition

According to the data, carbohydrates are the largest part of this snack bar.

Carbohydrates – 40%

Protein – 15%

Fat – 15%

Water – 30%

Note: Pie charts are best when you care about percent of a whole, not about change over time.

Notebook Task – Pie Chart Notes

Draw a circle and split it into four slices that roughly match the percentages above.
Color and label each slice. Write the percentage inside or next to it.
Answer these three questions under your drawing:
1. Which substance makes up the largest proportion?
2. What percentage of the sample is carbohydrates?
3. Which component contributes the smallest portion?
Write one sentence that starts with “According to the pie chart...”.

Practice – CAST-Style Pie Chart Questions

Use the pie chart and table above to answer these questions.

1. Which substance makes up the largest proportion of the snack bar?

Carbohydrates Protein Fat Water

2. A student writes: “According to the pie chart, 70% of the snack bar is water.”
Is this statement supported by the data?

Yes, because water is the biggest slice. Yes, because water and carbohydrates together equal 70%. No, the pie chart shows that water is only 30% of the snack bar. No, because pie charts cannot show percentages.

Continue to page 5

📚 Graphing Vocab 📈 Line Graphs 📊 Bar Graphs 🥧 Pie Charts 📉 Scatter Plots 🧮 Survival Curves