Most married couples have two or three personality preferences in common. A random sample of 382 married couples found that 136 had three preferences in common. Another random sample of 562 couples showed that 212 had two personality preferences in common. Let p1 be the population proportion of all married couples who have three personality preferences in common. Let p2 be the population proportion of all married couples who have two personality preferences in common. (a) Find a 99% confidence interval for p1 – p2. (Use 3 decimal places.) lower limit =__ upper limit =__
Most married couples have two or three personality preferences in common. A random sample of 382 married couples found that 136 had three preferences in common. Another random sample of 562 couples showed that 212 had two personality preferences in common. Let p1 be the population proportion of all married couples who have three personality preferences in common. Let p2 be the population proportion of all married couples who have two personality preferences in common.
| lower limit | =__ |
| upper limit | =__ |
The U.S. Geological Survey compiled historical data about Old Faithful Geyser (Yellowstone National Park) from 1870 to 1987. Let x1 be a random variable that represents the time interval (in minutes) between Old Faithful eruptions for the years 1948 to 1952. Based on 9440 observations, the sample mean interval was x1 = 63.6 minutes. Let x2 be a random variable that represents the time interval in minutes between Old Faithful eruptions for the years 1983 to 1987. Based on 24,053 observations, the sample mean time interval was x2 = 72.8 minutes. Historical data suggest that ?1 = 8.21 minutes and ?2 = 12.62 minutes. Let ?1 be the population mean of x1 and let ?2 be the population mean of x2.
| lower limit | =__ |
| upper limit | =__ |
Trending now
This is a popular solution!
Step by step
Solved in 2 steps with 1 images
