1.
Suppose we flip a coin 100 times and count 60 heads. Let \(p\) be the (unknown) probability that the coin comes up heads on a flip. Give an approximate 95% confidence interval for the value of \(p\text{.}\)
Section 4.2 Confidence Intervals
Text of section.
Exercises Exercises
2.
Suppose in a sample of 100 people, 12 are left-handed.
(a)
Give a 95% confidence interval for the proportion \(p\) of left-handed people.
(b)
Give a 90% confidence interval.
3.
The weights of five mice are measured and recorded below. Give a 95% confidence interval for the sample mean weight of mice. (Pretend 5 measurements is large enough for the CLT to apply.)
| mouse \(i\) | 1 | 2 | 3 | 4 | 5 |
|---|---|---|---|---|---|
| weight \(\widetilde{w}_i\) (g) | 26 | 32 | 33 | 20 | 29 |
4.
The heights of five plants are measured and recorded below. Give a 95% confidence interval around the sample mean for the heights of the plants. (Pretend 5 measurements is large enough for the CLT to apply.)
| plant \(i\) | 1 | 2 | 3 | 4 | 5 |
|---|---|---|---|---|---|
| height \(\widetilde{h}_i\) (in) | 15 | 14 | 18 | 21 | 17 |
