Name:_______________
Date:________________
4.9 𝑡 − scores and confidence intervals
Section 1: A random sample of people determines the number of years
of formal education which they received
(kindergarden − graduate school).
The number of years of education are as follows:
13 13 13 14 17 17 12 19 11 12 17 19 17
23 23 24 17
1. Construct a 50% Confidence Interval estimating the average number of
years of education
2. Construct a 70% Confidence Interval estimating the average number of
years of education
3. Construct a 90% Confidence Interval estimating the average number of
years of education
4. Construct a 98% Confidence Interval estimating the average number of
years of education
5. Construct a 99% Confidence Interval estimating the average number of
years of education
BONUS: How many pairs of fathers & sons have both been President of the
United States?
Section 2: The number of points scored by the Seattle SuperSonics in 10 games
are as follows:
98
95
105
110
113
103
122
99
88
107
6. Construct a 60% Confidence Interval estimating the average number of
points scored by the SuperSonics
7. Construct a 80% Confidence Interval estimating the average number of
points scored by the SuperSonics
8. Construct a 90% Confidence Interval estimating the average number of
points scored by the SuperSonics
9. Construct a 98% Confidence Interval estimating the average number of
points scored by the SuperSonics
10.Construct a 99% Confidence Interval estimating the average number of
points scored by the SuperSonics
SCIENCE BONUS: What are xylem?
Section 3: A simple random survey of 8 people determines the square footage of
each person’s home/apartment. The results are as follows:
750
1300
1420
2200
4575
1890
500
2640
11.Construct a 50% Confidence Interval estimating the average square footage
of a person’s house
12.Construct a 60% Confidence Interval estimating the average square footage
of a person’s house
13.Construct 70% Confidence Interval estimating the average square footage
of a person’s house
14.Construct a 80% Confidence Interval estimating the average square footage
of a person’s house
15.Construct a 90% Confidence Interval estimating the average square footage
of a person’s house
LITERATURE BONUS: Who wrote the book The Cuckoo’s Calling (2013)?