Practice Quartiles in Math

Use these practice problems to test your method after reviewing the concept explanation and worked examples.

Quick Recap

Quartiles divide an ordered data set into four equal parts: Q1 is the 25th percentile, Q2 is the median (50th), and Q3 is the 75th percentile.

Q1 = 25th percentile, Q2 = median (50th), Q3 = 75th percentile.

Example 1

easy
Find the quartiles Q_1, Q_2, and Q_3 for the data set: \{4, 7, 9, 11, 14, 18, 22, 25, 30\}.

Example 2

medium
A dataset of 10 values (sorted): \{2, 5, 8, 12, 15, 18, 21, 25, 30, 40\}. Find all quartiles and the five-number summary.

Example 3

medium
Find Q_1, Q_2, and Q_3 for the dataset: 4, 7, 8, 12, 15, 18, 21, 25, 30.

Example 4

easy
Find Q_1 and Q_3 for: \{10, 20, 30, 40, 50, 60, 70\}.

Example 5

hard
A student scores at the 75th percentile on a standardized test with scores \{45, 52, 60, 67, 72, 78, 83, 89, 95, 98\}. Confirm that Q_3 equals the 75th percentile score and find what percent of students scored below Q_1.