In: Math
The following data represent petal lengths (in cm) for independent random samples of two species of Iris.
Petal length (in cm) of Iris virginica: x1; n1 = 35
5.0 | 5.7 | 6.4 | 6.1 | 5.1 | 5.5 | 5.3 | 5.5 | 6.9 | 5.0 | 4.9 | 6.0 | 4.8 | 6.1 | 5.6 | 5.1 |
5.6 | 4.8 | 5.4 | 5.1 | 5.1 | 5.9 | 5.2 | 5.7 | 5.4 | 4.5 | 6.4 | 5.3 | 5.5 | 6.7 | 5.7 | 4.9 |
4.8 | 5.7 | 5.1 |
Petal length (in cm) of Iris setosa: x2; n2 = 38
1.6 | 1.6 | 1.4 | 1.5 | 1.5 | 1.6 | 1.4 | 1.1 | 1.2 | 1.4 | 1.7 | 1.0 | 1.7 | 1.9 | 1.6 | 1.4 |
1.5 | 1.4 | 1.2 | 1.3 | 1.5 | 1.3 | 1.6 | 1.9 | 1.4 | 1.6 | 1.5 | 1.4 | 1.6 | 1.2 | 1.9 | 1.5 |
1.6 | 1.4 | 1.3 | 1.7 | 1.5 | 1.6 |
(a) Use a calculator with mean and standard deviation keys to calculate x1, s1, x2, and s2. (Round your answers to two decimal places.)
x1 = | |
s1 = | |
x2 = | |
s2 = |
(b) Let μ1 be the population mean for
x1 and let μ2 be the
population mean for x2. Find a 99% confidence
interval for μ1 − μ2.
(Round your answers to two decimal places.)
lower limit= | |
upper limit= |