Data Representations: Foundations

[Video: Introduction to Data Representations]

Learn how to read and interpret different types of data representations commonly found on the SAT, including tables, bar graphs, line graphs, and circle graphs (pie charts).

Understanding Data Representations

Data representation questions on the SAT test your ability to:

Read and interpret data from tables and various types of graphs
Compare data points across different representations
Calculate percentages, ratios, and averages from given data
Identify trends and patterns in data

Common Types of Data Representations

Type	Description	When Used
Tables	Organizes data in rows and columns	Showing exact numerical values for multiple variables
Bar Graphs	Uses rectangular bars to represent quantities	Comparing discrete categories or groups
Line Graphs	Shows data points connected by line segments	Displaying trends over time
Circle Graphs (Pie Charts)	Divides a circle into sectors proportional to quantities	Showing parts of a whole

Key Takeaways

Always read the title, labels, and units on any graph or table
Pay attention to the scale on graph axes
For pie charts, remember all sectors must add up to 100%
When comparing data, make sure you're comparing the same units

Practice Question

The table below shows the number of books read by students in a class during a summer reading program.

Number of Books	Number of Students
0-2	5
3-5	12
6-8	8
9-11	3
12+	2

What percentage of the class read 6 or more books?

A) 13%

B) 26%

C) 43%

D) 52%

First, calculate the total number of students in the class by adding all the students in each category. Then, add up the number of students who read 6 or more books (this includes the last three categories). Finally, divide the number of students who read 6+ books by the total number of students and multiply by 100 to get the percentage.

Step 1: Calculate total number of students: 5 (0-2) + 12 (3-5) + 8 (6-8) + 3 (9-11) + 2 (12+) = 30 students

Step 2: Calculate number of students who read 6 or more books: 8 (6-8) + 3 (9-11) + 2 (12+) = 13 students

Step 3: Calculate percentage: (13 ÷ 30) × 100 ≈ 43.33%

The closest answer choice is C) 43%.