Recall that amount of dioxide (milligrams/liter) and presence/absence of crude oil was determined for each of 16 water specimens collected from a mine reservoir. The data are repeated in the accompanying table.
For Information: Refer to the Journal of Petroleum Geology (April 2010) study of the environmental factors associated with biodegradation in crude oil reservoirs, Exercise 2.29.
Dioxide Amount Crude Oil Present
3.3 ................................... No
0.5 ................................... Yes
1.3 ................................... Yes
0.4 ................................... Yes
0.1 ................................... No
4.0 ................................... No
0.3 ................................... No
0.2 ................................... Yes
2.4 ................................... No
2.4 ................................... No
1.4 ................................... No
0.5 ................................... Yes
0.2 ................................... Yes
4.0 ................................... No
4.0 ................................... No
4.0 ................................... No
a. Find the mean dioxide level of the 16 water specimens. Interpret this value.
b. Find the median dioxide level of the 16 water specimens. Interpret this value.
c. Find the mode of the 16 dioxide levels. Interpret this value.
d. Find the median dioxide level of the 10 water specimens with no crude oil present.
e. Find the median dioxide level of the 6 water specimens with crude oil present.
f. Compare the results, parts d and e. Make a statement about the association between dioxide level and presence/absence of crude oil.