Petroleum pollution in oceans is known to increase the growth of a certain bacteria. Brian did a project for his ecology class in which he made a bacteria count (per 100 milliliters) in nine random samples of sea water. His counts gave the following readings:
17, 23, 18, 19, 21, 16, 12, 15, 18
a) Find the range.
b) Find the sample mean.
c) Find the median.
d) Find the mode.
e) Find the sample standard deviation.
a) The range is 21 – 12 = 9.
b) The sample mean is
c) The median is 17.5 as well.
d) The mode is 18.
e) The sample standard deviation is