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Session 7: Comparing Two Groups

Grade 4 Data Science · Double Bar Charts & Comparison Writing

Vocabulary — Fill in the Definitions
Double Bar Chart
Legend
Comparison
Category

1 Build a Double Bar Chart

Use the data table to build a double bar chart. Color Class A bars dark blue and Class B bars light blue. Add a legend and a title.

Pet 🔵 Class A 🩵 Class B
Dog128
Cat711
Fish46
Bird35
Other24
Favorite Pet — Class A vs. Class B
0 2 4 6 8 10 12 14 Number of Students Dog Cat Fish Bird Other Pet Type Class A (dark blue) Class B (light blue) ▶ Color in each bar to the correct height using the data table above
Class A = Dark Blue Class B = Light Blue

2 Read the Chart — Answer These Questions

Pet Class A Class B Difference (A − B) Which is higher?
Dog128 __________
Cat711 __________
Fish46 __________
Bird35 __________
Other24 __________

① Which pet had the biggest difference between the two classes?

② Which pet had the smallest difference? How small was the gap?

③ In which pet category did Class B clearly win? In which did Class A clearly win?

④ If you combined both classes, how many total students prefer Fish? Show your work.

Class A Fish: _____ + Class B Fish: _____ = _____ total students

3 Write 3 Comparison Statements

Use the sentence frames below to write 3 comparison statements about your chart. Include the actual numbers in each sentence.

___ preferred ___ more than ___ — ___ students vs. ___ students.
___ had the most ___ fans, while ___ had the most ___ fans.
Both classes had ___ as one of their top/bottom choices.
The biggest difference was for ___, with a gap of ___ students.
Statement 1
Statement 2
Statement 3

🤔 Reflection: Which comparison surprised you most? Why?

4 Think Deeper — Fair Comparisons

Class A has 28 students total. Class B has 34 students total. This means raw numbers might not be totally fair to compare.

Complete the fractions for cats:

Class A cats as a fraction: 7 out of 28 = _____ out of every 4 students
Class B cats as a fraction: 11 out of 34 ≈ _____ out of every 4 students (estimate)

After looking at these fractions, does Class B still seem more into cats than Class A? Explain.

Why is it important to know how many students were in each class before comparing?

🏠 Take-Home Challenge

Survey 5 people at home and 5 people at school about their favorite season: Spring · Summer · Fall · Winter. Record your results:

Season Spring Summer Fall Winter
Home (5)
School (5)

Write one comparison sentence about your results:

Grade 4 Data Science · Session 7 · Comparing Two Groups · sdabagh.github.io