# Question: Tills are glacial drifts consisting of a mixture of clay

Tills are glacial drifts consisting of a mixture of clay, sand, gravel, and boulders. Engineers from the University of Washington’s Department of Earth and Space Sciences studied the chemical makeup of buried tills in order to estimate the age of the glacial drifts in Wisconsin (American Journal of Science, Jan. 2005). The ratio of the elements aluminum (AI) and beryllium (Be) in sediment is related to the duration of burial. The Al–Be ratios for a sample of 26 buried till specimens are given in the accompanying table and saved in the TILLRATIO file. An SPSS printout with descriptive statistics for the Al–Be ratio is shown at the bottom of the page.

a. Find and interpret the z-score associated with the largest ratio, the smallest ratio, and the mean ratio.

b. Would you consider the largest ratio to be unusually large? Why or why not?

c. Construct a box plot for the data and identify any outliers.

a. Find and interpret the z-score associated with the largest ratio, the smallest ratio, and the mean ratio.

b. Would you consider the largest ratio to be unusually large? Why or why not?

c. Construct a box plot for the data and identify any outliers.

## Answer to relevant Questions

Refer to the data on sanitation levels of cruise ships, presented in Exercise. These data are saved in the SHIPSANIT file. a. Use the box plot method to detect any outliers in the data. b. Use the z-score method to detect ...The Colorado Rockies play their major league home baseball games in Coors Field, Denver. Each year, the Rockies are among the leaders in team batting statistics (e.g., home runs, batting average, and slugging percentage). ...For each of the data sets in parts a–d, compute x-bar, s2, and s. a. 13, 1, 10, 3, 3 b. 13, 6, 6, 0 c. 1, 0, 1, 10, 11, 11, 15 d. 3, 3, 3, 3 e. For each of the data sets in parts a–d, form the interval x-bar ± ...Three-way catalytic converters have been installed in new vehicles in order to reduce pollutants from motor vehicle exhaust emissions. However, these converters unintentionally increase the level of ammonia in the air. ...Compute each of the following: a. b. c. d. e.Post your question