1. A
professor investigated the fieldwork methods used by qualitative sociologists.
Searching for all published journal articled, dissertations, and conference
proceedings over the previous seven years, she discovered that fieldwork
methods could be categorized. Use the data table to complete parts a through c.
Fieldwork 
Number 
Interview 
24 
Observation 
29 
Observation 
15 
Grounded 
10 
Total 
78 
a. Find
the relative frequency of the number of papers for each fieldwork method
category
Fieldwork 
Interview 
Observation 
Observation 
Grounded 
(Round to the nearest thousandth as needed)
2. A magazine published a study on the
ammonia levels near the exit ramp of a highway tunnel. The date in the teble
represents daily ammonia concentrations (in parts per million) on eight random
selected days during thr afternoon drive time.
Complete part a through c:
1.51 
1.48 
1.37 
1.49 
1.63 
1.43 
1.42 
1.45 
a.
Find
the range of the ammonia levels. Give
the units of measurements for the range
The
range is ——— ppm or ppm squared (
type an integer or a decimal)
b.
find the variance of the ammonia levels.
If possible give units of measurement for the variance
The
variance is _____ with ____ units of ppm squared or ppm (round to four decimal
places as needed)
c.
Find the standard deviation of the ammonia levels. Give the units of measurement for the
standard deviation
The
standard deviation is ___________ ppm or ppm squared (round to three decimal
places as needed)
3. If x is binomial random variable, compute p(x) for each of the cases below.
a. N=5, x=1, p=0.3;
b. N=4, x=2, q=0.2;
c. N=3, x=0, p=0.7;
d. N=5, x=3, p=0.4;
e. N=4, x=2, q=0.8;
f. N=3, x=1, p=0.9.
a. p(x) = — (Round to four decimal
places as needed)
b. p(x) = — (Round to four decimal
places as needed)
c. p(x) = — (Round to four decimal
places as needed)
d. p(x) = — (Round to four decimal
places as needed)
e. p(x) = — (Round to four decimal
places as needed)
f. p(x) = — (Round to four decimal
places as needed)
4. A national standard requires that public bridges over 20 feet in length must
be inspected and rated every 2 years. The rating scale ranges from 0 (poorest
rating) to 9 (highest rating). A group of engineers used a probabilistic model
to forecast the inspection ratings of all major bridges in a city. For the year
2020, the engineers forecast that 5% of all major bridges in that city will
have ratings of 4 or below. Complete parts a and b.
a. Use the forecast to find the
probability that in a random sample of 9 major bridges in the city at least 3
will have an inspection rating of 4 or below in 2020
P(x > 3) = — (round to five decimal places as needed)
5. Find a value of a standard normal random variable Z,
A. P(Z > 1.70) B. P(Z<
1.42) C. P(0.39 < Z <
2.63)
d. P(2.46 < Z < 1.68) (Round to
three decimal places as needed)
6.) Find a
value of the standard normal random variable Z, Call it Z0 (z subzero), such
that the following probabilities are satisfied
a.
P(Z ? Z0) = 0.7286
b.
P( Z0 ? Z ? Z0) = 0.8358
c.
P( Z0 ? Z ? 0) = 0.4568
d.
P( 1 < Z < Z0) = 0.6097
a.
Z0 = _____ b. Z0 = _____ c. Z0 = _____ d. Z0 = _____ (Round to two decimal
places as needed)
Please note the 0s beside the Zs are subzero,
7.)
Financial analysts who make forecasts of stock prices are categorized as either
“buyside” analysts or “sell side” analysts. The mean and
standard deviation of the forecast errors for both types of analysts are shown
in the table to the right. Assume that the distribution of forecast errors are
approx normally distributed:
Buy Side 
Sell side 

Mean 
0.87 
0.06 
Standard Deviation 
1.94 
0.81 
a.
Find the probability that a buy side analyst has a forecast error of +2.00 or
higher
b.
Find the probability that a sell side analyst has a forecast error of +2.00 or
higher
View
the table of areas under the table of standardized normal curve below
a.
The probability that a buy side analyst has a forecast error of +2.00 or higher
is _____. (Round to three decimal places
as needed)
b.
The probability that a sell side analyst has a forecast error of +2.00 or
higher is _____.(Round to three decimal
places as needed)
Z 
0.00 
0.01 
0.02 
0.03 
0.04 
0.05 
0.06 
0.07 
0.08 
0.09 
0.0 
0.0000 
0.0040 
0.0080 
0.0120 
0.0160 
0.0199 
0.0239 
0.0279 
0.0319 
0.0359 
0.1 
0.0398 
0.0438 
0.0478 
0.0517 
0.0557 
0.0596 
0.0636 
0.0675 
0.0714 
0.0753 
0.2 
0.0793 
0.0832 
0.0871 
0.0910 
0.0948 
0.0987 
0.1026 
0.1064 
0.1103 
0.1141 
0.3 
0.1179 
0.1217 
0.1255 
0.1293 
0.1331 
0.1368 
0.1406 
0.1443 
0.1480 
0.1517 
0.4 
0.1554 
0.1591 
0.1628 
0.1664 
0.1700 
0.1736 
0.1772 
0.1808 
0.1844 
0.1879 
0.5 
0.1915 
0.1950 
0.1985 
0.2019 
0.2054 
0.2088 
0.2123 
0.2157 
0.2190 
0.2224 
0.6 
0.2257 
0.2291 
0.2324 
0.2357 
0.2389 
0.2422 
0.2454 
0.2486 
0.2517 
0.2549 
0.7 
0.2580 
0.2611 
0.2642 
0.2673 
0.2704 
0.2734 
0.2764 
0.2794 
0.2823 
0.2852 
0.8 
0.2881 
0.2910 
0.2939 
0.2967 
0.2995 
0.3023 
0.3051 
0.3078 
0.3106 
0.3133 
0.9 
0.3159 
0.3186 
0.3212 
0.3238 
0.3264 
0.3289 
0.3315 
0.3340 
0.3365 
0.3389 
1.0 
0.3413 
0.3438 
0.3461 
0.3485 
0.3508 
0.3531 
0.3554 
0.3577 
0.3599 
0.3621 
1.1 
0.3643 
0.3665 
0.3686 
0.3708 
0.3729 
0.3749 
0.3770 
0.3790 
0.3810 
0.3830 
1.2 
0.3849 
0.3869 
0.3888 
0.3907 
0.3925 
0.3944 
0.3962 
0.3980 
0.3997 
0.4015 
1.3 
0.4032 
0.4049 
0.4066 
0.4082 
0.4099 
0.4115 
0.4131 
0.4147 
0.4162 
0.4177 
1.4 
0.4192 
0.4207 
0.4222 
0.4236 
0.4251 
0.4265 
0.4279 
0.4292 
0.4306 
0.4319 
1.5 
0.4332 
0.4345 
0.4357 
0.4370 
0.4382 
0.4394 
0.4406 
0.4418 
0.4429 
0.4441 
1.6 
0.4452 
0.4463 
0.4474 
0.4484 
0.4495 
0.4505 
0.4515 
0.4525 
0.4535 
0.4545 
1.7 
0.4554 
0.4564 
0.4573 
0.4582 
0.4591 
0.4599 
0.4608 
0.4616 
0.4625 
0.4633 
1.8 
0.4641 
0.4649 
0.4656 
0.4664 
0.4671 
0.4678 
0.4686 
0.4693 
0.4699 
0.4706 
1.9 
0.4713 
0.4719 
0.4726 
0.4732 
0.4738 
0.4744 
0.4750 
0.4756 
0.4761 
0.4767 
2.0 
0.4772 
0.4778 
0.4783 
0.4788 
0.4793 
0.4798 
0.4803 
0.4808 
0.4812 
0.4817 
2.1 
0.4821 
0.4826 
0.4830 
0.4834 
0.4838 
0.4842 
0.4846 
0.4850 
0.4854 
0.4857 
2.2 
0.4861 
0.4864 
0.4868 
0.4871 
0.4875 
0.4878 
0.4881 
0.4884 
0.4887 
0.4890 
2.3 
0.4893 
0.4896 
0.4898 
0.4901 
0.4904 
0.4906 
0.4909 
0.4911 
0.4913 
0.4916 
2.4 
0.4918 
0.4920 
0.4922 
0.4925 
0.4927 
0.4929 
0.4931 
0.4932 
0.4934 
0.4936 
2.5 
0.4938 
0.4940 
0.4941 
0.4943 
0.4945 
0.4946 
0.4948 
0.4949 
0.4951 
0.4952 
2.6 
0.4953 
0.4955 
0.4956 
0.4957 
0.4959 
0.4960 
0.4961 
0.4962 
0.4963 
0.4964 
2.7 
0.4965 
0.4966 
0.4967 
0.4968 
0.4969 
0.4970 
0.4971 
0.4972 
0.4973 
0.4974 
2.8 
0.4974 
0.4975 
0.4976 
0.4977 
0.4977 
0.4978 
0.4979 
0.4979 
0.4980 
0.4981 
2.9 
0.4981 
0.4982 
0.4982 
0.4983 
0.4984 
0.4984 
0.4985 
0.4985 
0.4986 
0.4986 
3.0 
0.4987 
0.4987 
0.4987 
0.4988 
0.4988 
0.4989 
0.4989 
0.4989 
0.4990 
0.4990 
8. The mean gas mileage for a hybrid car is
57 miles per gallon. Suppose that the gasoline mileage is approximately normally
distributed with a standard deviation of 3.5 miles per gallon.
a.What is the probability that a randomly
selected hybrid gets more than 60 mpg?
b. What is the probability that a randomly
selected hybrid gets 53 mpg or less?
c. What is the probability that a randomly
selected hybrid gets between 58 and 61 mpg?
d. What is the probability that a randomly
selected hybrid gets less than 46 miles per gallon?