MIDTERM EXAM INTRODUCTION TO STATISTICS
NAME_______eino______________________________________________________
Answer the questions on the exam sheets showing the working out. Total time 90
minutes.
1. (1.5 points) The community of homeowners has asked a series of questions to the residents
of an urbanization. Identify the type of data (variable) requested in each question.
a. Did you play golf last month on the new golf course in the urbanization?
b. How many times have you eaten in the restaurant of the urbanization in the last three
months?
c. Do you have a caravan?
d. Rate the new security system of the urbanization (very good, good, bad, very bad).
2. (2.5 points) Calculate the range, the mean, the mode, the median and the standard deviation
of the following sample data: 6 8 7 10 3 5 9 8 (show the working out)
Lowest to highest
3 5 6 7 8 8 9 10
Range = 10 - 3
Average = 3 + 5 + 6 + 7 + 8 + 8 + 9 + 10 / 8 = 7
Median = 7 + 8 / 2 = 7,5
Variance = (-4)^2 + (-2)^2 + (-1)^2 + 0^2 + 1^2 + 1^2 + 2^2 + 3^2 / 7 = 5,14
Standard Deviation = √ sx^2 = √5,14 = 2,27
