Math 1 · Unit 12 · Lesson 3 · part 4 of 4
Practice Problems
Try them, get help one step at a time, then print how it went.
Practice: try it, then get help one step at a time
The IQR by hand, the standard deviation by hand once and then with the tool, and deciding which set is more spread out. Hint gives a nudge, Show next step shows one worked step at a time, Reveal answer checks, and Hide help / start over clears the card.
My results
Finished the practice? Print a page that shows each question, what you typed or chose, the correct answer, and how it went. Good for showing a teacher or keeping in a folder.
Exit ticket
On paper or an index card. Use the math word and the plain-English word.
- Find Q1, Q3, and the IQR of 4, 5, 6, 7, 8.
- For 2, 4, 6, 8, 10, the squared distances from the mean add to 40. Find σ and s.
- Two sets have the same mean, with standard deviations 1.4 and 3.7. What does that tell you?
- When do you divide by n, and when by n − 1?
Check your exit ticket
- Q1 = 4.5, Q3 = 7.5, IQR = 3.
- σ = √8 ≈ 2.83; s = √10 ≈ 3.16.
- The second is more spread out: its values are typically farther from the mean.
- By n for a whole group (σ); by n − 1 for a sample (s).