Problem #1. Suppose a student is interested in the price of a gallon of Gas in PA. To investigate it, the student visited 20 gas stations in Lehigh Valley and collected the prices of a gallon of Gas. He chose to go to those gas stations because they were close to his dormitory housing.

i. What is the population of units?

Gas stations

ii. What is the variable of interest?

iii. What is the type of variable in sub-question 2?

iv. What is the statistical population?

v. What is the sample?

vi. What is the sampling method used in this investigation? Why do you think so?

Problem #2. In the MATH12 beginning semester survey, each student was asked about the number of pets in their family. For convenience, 36 survey observations are provided as follows:

1 2 1 1 3 0 3 1 2

2 1 1 4 2 1 1 0 2

0 2 2 0 1 1 1 2 0

2 0 1 0 1 1 1 2 5

i. What is the type of the variable?

ii. Make a frequency table.

iii. Make a line diagram.

iv. Comment on the shape of the distribution.

Problem #3. In Fall 2009, the National College Health Assessment conducted a study including a random sample of 11,728 American college males and asked whether they were 'verbally threatened within the last 1 year'.

i. What is the population of units?

1

ii. What is the variable of interest?

iii. What is the type of variable in sub-question 2?

iv. What is the statistical population?

v. What is the sample?

vi. What is the sampling method used in this investigation? Why do you think so?

Problem #4. In a recent year, 35 sites around the world experienced earthquakes of magnitude greater than 6.5.

6.6 6.6 6.6 6.6 6.6 6.6 6.7 6.7 6.7

6.7 6.7 6.8 6.8 6.8 6.9 6.9 6.9 6.9

7.0 7.0 7.0 7.0 7.1 7.1 7.1 7.2 7.2

7.5 7.6 7.7 7.8 7.8 7.8 7.9 7.9

i. Make a frequency table with the following left-open sub-intervals:

(6.5,6.8], (6.8,7.1], (7.1,7.4], (7.4,7.7], and (7.7,8.0].

ii. Based on the frequency table, construct a histogram.

Problem #5. Summation with notation.

SupposeXis a variable with the following measurements:{3, 1, 5, 2, 2}.

_i.!⁵_i=1x_i=

_ii.!⁴_i=1x²_i=

_iii.!⁵_i=1(x_i/100) =

_iv.!⁵_i=1"_xⁱ₅^#=

_v.!⁵_i=1(x_i3) =