14.     The article “Hydrogeochemical Characteristics of Groundwater in a Mid-Western Coastal Aquifer Sys- tem” (S. Jeen, J. Kim, et  al.,  Geosciences  Jour- nal, 2001:339–348) presents measurements of various properties of shallow groundwater in a certain aquifer system in Korea. Following are measurements of elec- trical conductivity (in microsiemens per centimeter) for 23 water samples.

 

 

 

tive frequency for a given class interval are the sums	2099	528	2030	1350	1018	384	1499
of the frequencies and relative frequencies,    respec-	1265	375	424	789	810	522	513
tively, over all classes up to and including the  given	488	200	215	486	257	557	260
class. For example, if there are five classes, with fre-	461	500
quencies 11, 7, 3, 14, and 5, the cumulative frequen-

 

cies would be 11, 18, 21, 35, and 40, and the cu- mulative relative frequencies would be 0.275, 0.450,

 

a.    Find the mean.

 

b.    Find the standard deviation.

 

 

 

c.    Find the median.

 

d.    Construct a dotplot.

 

e.    Find the first quartile.

 

f.    Find the third quartile.

 

g.    Find the interquartile range.

 

h.    Construct a boxplot.

 

i.    Which of the points, if any, are outliers?

 

j.    If a histogram were constructed, would it be skewed to the left, skewed to the right, or approx- imately symmetric?