Math 1P98
December 11 2004
page 2 of 17
1.
Which sample of prices has its mean $2 greater than its standard deviation?
a. $1, $4, $7
b. $2, $5, $8
c. $7, $9, $12
d. $1, $3, $4
e.$22, $24, $2
2.
Which sample of weights, g,
has a median 1 g larger than the mode.
a. 2,5,1,7,5
b. 3, 2, 4, 3, 6
c, 5, 1, 7, 3, 3
d. 10, 12, 5, 3, 12
e. 5, 3, 8, 2, 2
3.
a.
b.
c.
d.
Three of the above histograms represent samples of 30 random data from a normal
distribution with
ì
= 50 and
ó
= 1, 10 and 15.
The other one represents the sampling
distribution of means of sample size n = 10 taken from a normal distribution with
ì
= 50
and
ó
= 10 . Which represents the sampling distribution of means?
..........................................................................................................................................
4-7 .
Use the following descriptive statistics data for the next four questions.
Descriptive Statistics
Variable
N
Mean
Median
TrMean
StDev
SE Mean
speed
40
57.24
56.68
56.82
11.54
1.82
Minimum
Maximum
Q1
Q3
38.93
84.32
49.40
63.73
4.
(3 marks) The speed of cars passing a residential area forms a normal distribution.
Using the Descriptive Statistics for the measured speed (km/hr) of a sample of these
cars, find the 95% confidence interval for the mean car speed in this area.
a. 53.7 to 60 .8 km/hr
b. 3.58 km/hr
c. 54.3 to 61.7 km/hr
d. 54.24 to 60.2 km/hr