Homework #2
10 Questions, 2 points per question, 20 points total
Chapter Three
1. Scores on a test have a mean of 66 and a standard deviation of 9. Michelle has a score of 57.
Convert Michelle’s score to a z score.
A) 9
B) –1 C) 1
D) –9
2. The owner of a pharmaceutical company employs eighty people. As part of their personnel file,
she asked each one to record to the nearest one-tenth of a mile the distance they travel one way
from home to work. The distances for a random sample of six employees are listed below: 26 32
29 16 45 19 Find the variance for the given data.
A) 18.9
B) 5043.6
C) 15.8
D) 107.0
3. The ages (in years) when patients were administered the shingles vaccine are listed below. Find
the mode(s) for the given sample data. 51 61 62 57 50 67 68 58 53
A) 51 yr, 61 yr, 62 yr, 57 yr, 50 yr, 67 yr, 68 yr, 58 yr, 53 yr
B) 58 yr
C) 58.6 yr
D) no mode
4. Jorge has his own business as a massage therapist. The amounts he made in the last five months
are shown below: $2426 $2463 $1451 $2154 $1119 Find the mean, median, and range of the
data.
A) Mean = $1923, Median = $2154, Range = $1344
B) Mean = $2154, Median = $1923, Range = $1344
C) Mean = $1923, Median = $2154, Range = – $1344
5. The fees for veterinary surgeries last month are listed below:
$2894.21
$1786.37
$1777.15
$3296.69
$2144.77
$4086.27
$4096.37
$2784.22
$4046.29
$4027.79
What was the mean cost for a surgery? Round your answer to the nearest cent.
6.
7. Which of the following is not a property of variance?
A) The units of variance are the squares of the units of the original data.
B) The value of the variance is always positive or 0.
C) The sample variance is a biased estimator of the population variance.
D) The value of the variance is zero only when all of the data values are the same number.
8. How will a high outlier in a data set affect the mean and median?
A) Distribution skewed to the right, mean pulled to the right, median not effected
B) Distribution skewed to the right, mean not effected, median skewed to the right
C) Distribution skewed to the left, mean pulled to the left, median not effected
D) Distribution skewed to the right, mean not effected, median not effected
9. An ENT physician has daily mean billings of $ 28,372.72. The standard deviation of the billings is
$2000. On Tuesday, the physician billed $34,885.21 worth of procedures. Find Tuesday's z score.
Was Tuesday a significantly good day?
A) 3.26, yes
B) 3.42, no
C) 2.61, no
D) 3.57, yes
10.