Stretch: How Many Observations?
I can report the number of observations (the count of data values) in a data set.
🧠 The Challenge
data setobservationcountsample size
The number of observations is how many data values were collected — the size of the data set. Repeated values still count separately.
👀 Worked Example
The data set {4, 7, 2, 9, 5} has 5 observations. The set {10, 10, 10} has 3 observations (repeats count).
✏️ Your Turn
0 of 3 checks complete
1. How many observations are in {3, 6, 1, 8}?
2. A survey records 12 students' heights. How many observations?
3. How many observations are in {10, 10, 10}?
💬 Explain Your Thinking
Explain how to count the observations in {5, 2, 5, 8}:
"I count each value, including repeats: the set {5, 2, 5, 8} has blank observations."