Question

In a recent issue of the IEEE Spectrum, 84 engineering conferences were announced. Four conferences lasted two days. Thirty-six lasted three days. Eighteen lasted four days. Nineteen lasted five days. Four lasted six days. One lasted seven days. One lasted eight days. One lasted nine days. Let X = the length (in days) of an engineering conference.

• Part (a)

  Organize the data in a chart. (Round your answers to four decimal places.)

  X	Frequency	Relative Frequency	Cumulative Relative Frequency
  2	4	0.0476	0.0476
  3	36	0.4286	0.4762
  4	18	0.2143	0.6905
  5	19	0.2262	0.9167
  6	4	0.0476	0.9643
  7	1	0.0119	0.9762
  8	1	0.0119	0.9881
  9	1	0.0119	1

• Find the 55th percentile.
  days

• Find the 40th percentile.
  days

• The middle 50% of the conferences last from ____ days to _____ days.

• Calculate the sample mean of days of engineering conferences. (Round your answer to two decimal places.)
  ______days

• Calculate the sample standard deviation of days of engineering conferences. (Round your answer to two decimal places.)
  ______ days

• Find the mode.
  ______ days

Answer 1