The Real Property Association of Canada surveyed 82 office buildings as to their water usage and obtained the following results in terms of the number of litres of water used per square foot of office space per year (L/ft²/yr) normalized for type of building:

a) Taking into account the number of buildings surveyed, draw a histogram of this data. Identify the mode of the histogram.

b) Using the midpoint of each range, and assuming that the average water use of buildings over 200 L/ft²/yr is 300 L/ft²/yr, estimate the mean and the standard deviation of the water usage of the office buildings surveyed.

c) Again, using the midpoint of each range, calculate the quartiles and median of this data. Identify how many buildings are outliers.

Transcribed Image Text:

Water Usage (L/ft?/yr) Water Usage (L/ft?/yr) Number of Number of Buildings Buildings 0-19 100-119 20-39 11 120-139 40-59 11 140-159 2 60-79 22 160-179 2 80-99 14 180-199 10 >200