│ ACTIVITIES 509
ACTIVITY 1.3
1. {1, 17, 17, 17, 14, 10, 15, 6}
Answers will vary. This list is a random sample taken with replacement because 17 appears three
times.
ACTIVITY 2.3
1. When the mean is equal to the median, the shape of the distribution will be symmetric.
When a few points are added that are less than 10, the mean and median both decrease slightly.
As you continue to add points that are less than 10, the median will decrease dramatically and the
mean will also decrease, but to a lesser degree.
ACTIVITY 2.4
1. When a point with a value of 15 is added, the mean remains constant and the standard deviation
decreases. When a point with a value of 20 is added, the mean is raised and the standard deviation
increases. (Answers will vary.)
ACTIVITY 3.1
1. Answers will vary.
510 ACTIVITIES │
ACTIVITY 3.3
1. P(3 or 4) 111
663
=+=
ACTIVITY 4.2
1. Answers will vary. {7, 8, 7, 7, 7, 7, 8, 8, 9, 10}
(a) P(x = 5) = 0
10
(b) P(x ≥ 8) = 5
10
(c) P(x ≤ 7) = 5
10
ACTIVITY 5.4
1. The mean of the sampling distribution of a uniform, bell-shaped, and skewed distribution will be
approximately 25.
│ ACTIVITIES 511
ACTIVITY 6.2
1. Approximately 95% of the z and t confidence intervals will contain the mean of 25.
ACTIVITY 6.3
1. Approximately 95% and 99% of the CI’s will contain 0.6.
ACTIVITY 7.3
1. At 0.05α=, approximately 50 of the 1000 null hypotheses will be rejected.
At 0.01α=, approximately 10 of the 1000 null hypotheses will be rejected.
ACTIVITY 7.4
1. Approximately 50 null hypotheses will be rejected at the 0.05 level while approximately 10 null
hypotheses will be rejected at the 0.01 level.
ACTIVITY 9.1
1. If the scatter plot is linear with a positive slope, 1r≈. If the scatter plot is linear with a negative
slope, 1r≈− .
512 ACTIVITIES │
3. Create a data set that is nonlinear.
4. 0.9r≈− has a negative slope while using 0.9r≈ will have a positive slope.
ACTIVITY 9.2
1. Answers will vary.