STATISTICS BEC1 STATISTICS FINAL EXAM
SOLUTIONS WGU PRACTICE
EXAMINATION SCRIPT 2026 DETAILED
ANSWERS GRADED A+
⩥ Professor Gill is designing a multiple-choice test. There are to be 10
questions. Each question is to have five choices for answers. The choices
are to be designated by the letters a, b, c, d, and e. Professor Gill wishes
to use a random-number table to determine which letter choice should
correspond to the correct answer for a question. Using the number
correspondence 1 for a, 2 for b, 3 for c, 4 for d, and 5 for e, use a
random-number table to determine the letter choice for the correct
answer for each of the 10 questions. Answer: 1.2.17
⩥ A study involves three variables: income level, hours spent watching
TV per week, and hours spent at home on the Internet per week. List
some ways the variables might be confounded. Answer: 1.3.1
⩥ Zane is examining two studies involving how different generations
classify specified items as either luxuries or necessities. In the first
study, the Echo generation is defined to be people ages 18-29. The
second study defined the Echo generation to be people ages 20-31. Zane
notices that the first study was conducted in 2006 while the second one
was conducted in 2008.
,(a) Are the two studies inconsistent in their description of the Echo
generation?
(b) What are the birth years of the Echo generation? Answer: 1.3.5
⩥ Which technique for gathering data (observational study or
experiment) do you think was used in the following studies?
(a) The Colorado Division of Wildlife netted and released 774 fish at
Quincy Reservoir. There were 219 perch, 315 blue gill, 83 pike, and 157
rainbow trout.
(b) The Colorado Division of Wildlife caught 41 bighorn sheep on Mt.
Evans and gave each one an injection to prevent heartworm. A year later,
38 of these sheep did not have heartworm, while the other three did.
(c) The Colorado Division of Wildlife imposed special fishing
regulations on the Deckers section of the South Platte River. All trout
under 15 inches had to be released. A study of trout before and after the
regulation went into effect showed that the average length of a trout
increased by 4.2 inches after the new regulation.
(d) An ecology class used binoculars to watch 23 turtles at Lowell
Ponds. It was found that 18 were box turtles Answer: 1.3.7
⩥ A data set with whole numbers has a low value of 20 and a high value
of 82. Find the class width and class limits for a frequency table with 7
classes. Answer: 2.1.5
,⩥ You are manager of a specialty coffee shop and collect data
throughout a full day regarding waiting time for customers from the time
they enter the shop until the time they pick up their order.
(a) What type of distribution do you think would be most desirable for
the wait- ing times: skewed right, skewed left, mound-shaped
symmetrical? Explain.
(b) What if the distribution for waiting times were bimodal? What might
be some explanations? Answer: 2.1.7
⩥ How long does it take to finish the 1161-mile Iditarod Dog Sled Race
from Anchorage to Nome, Alaska (see Viewpoint)? Finish times (to the
nearest hour) for 57 dogsled teams are shown below.
261 271 236 244 279 296 284 299 288 338 360 341 333 261 266 287
296 313 299 303 277 283 304 305 288 290 288 332 330 309 328 307
328 285 291 295 310 318 318 320 333 321 323 324 327
Use five classes.
a) Find the class width.
(b) Make a frequency table showing class limits, class boundaries,
midpoints, frequencies, relative frequencies, and cumulative frequencies.
(c) Draw a histogram.
(d) Draw a relative-frequency histogram.
(e) Categorize the basic distribution shape as uniform, mound-shaped
sym-
metrical, bimodal, skewed left, or skewed right.
(f) Draw an ogive. Answer: 2.1.15
, ⩥ Certain kinds of tumors tend to recur. The following data represent the
lengths of time, in months, for a tumor to recur after chemotherapy. Use
five classes.
19 18 50 1 14 45 38 40 27
20 17 1 21 22 54 46 25 49
59 39 43 39 5 9 38 18 54
59 46 50 29 12 19 36 43
41 10 50 41 25 19 39
a) Find the class width.
(b) Make a frequency table showing class limits, class boundaries,
midpoints, frequencies, relative frequencies, and cumulative frequencies.
(c) Draw a histogram.
(d) Draw a relative-frequency histogram.
(e) Categorize the basic distribution shape as uniform, mound-shaped
sym-
metrical, bimodal, skewed left, or skewed right.
(f) Draw an ogive. Answer: 2.1.17
⩥ It is costly in both time and money to go to college. Does it pay off?
According to the Bureau of the Census, the answer is yes. The average
annual income (in thousands of dollars) of a household headed by a
person with the stated education level is as follows: 21.6 if ninth grade is
the high- est level achieved, 39.6 for high school graduates, 56.8 for
SOLUTIONS WGU PRACTICE
EXAMINATION SCRIPT 2026 DETAILED
ANSWERS GRADED A+
⩥ Professor Gill is designing a multiple-choice test. There are to be 10
questions. Each question is to have five choices for answers. The choices
are to be designated by the letters a, b, c, d, and e. Professor Gill wishes
to use a random-number table to determine which letter choice should
correspond to the correct answer for a question. Using the number
correspondence 1 for a, 2 for b, 3 for c, 4 for d, and 5 for e, use a
random-number table to determine the letter choice for the correct
answer for each of the 10 questions. Answer: 1.2.17
⩥ A study involves three variables: income level, hours spent watching
TV per week, and hours spent at home on the Internet per week. List
some ways the variables might be confounded. Answer: 1.3.1
⩥ Zane is examining two studies involving how different generations
classify specified items as either luxuries or necessities. In the first
study, the Echo generation is defined to be people ages 18-29. The
second study defined the Echo generation to be people ages 20-31. Zane
notices that the first study was conducted in 2006 while the second one
was conducted in 2008.
,(a) Are the two studies inconsistent in their description of the Echo
generation?
(b) What are the birth years of the Echo generation? Answer: 1.3.5
⩥ Which technique for gathering data (observational study or
experiment) do you think was used in the following studies?
(a) The Colorado Division of Wildlife netted and released 774 fish at
Quincy Reservoir. There were 219 perch, 315 blue gill, 83 pike, and 157
rainbow trout.
(b) The Colorado Division of Wildlife caught 41 bighorn sheep on Mt.
Evans and gave each one an injection to prevent heartworm. A year later,
38 of these sheep did not have heartworm, while the other three did.
(c) The Colorado Division of Wildlife imposed special fishing
regulations on the Deckers section of the South Platte River. All trout
under 15 inches had to be released. A study of trout before and after the
regulation went into effect showed that the average length of a trout
increased by 4.2 inches after the new regulation.
(d) An ecology class used binoculars to watch 23 turtles at Lowell
Ponds. It was found that 18 were box turtles Answer: 1.3.7
⩥ A data set with whole numbers has a low value of 20 and a high value
of 82. Find the class width and class limits for a frequency table with 7
classes. Answer: 2.1.5
,⩥ You are manager of a specialty coffee shop and collect data
throughout a full day regarding waiting time for customers from the time
they enter the shop until the time they pick up their order.
(a) What type of distribution do you think would be most desirable for
the wait- ing times: skewed right, skewed left, mound-shaped
symmetrical? Explain.
(b) What if the distribution for waiting times were bimodal? What might
be some explanations? Answer: 2.1.7
⩥ How long does it take to finish the 1161-mile Iditarod Dog Sled Race
from Anchorage to Nome, Alaska (see Viewpoint)? Finish times (to the
nearest hour) for 57 dogsled teams are shown below.
261 271 236 244 279 296 284 299 288 338 360 341 333 261 266 287
296 313 299 303 277 283 304 305 288 290 288 332 330 309 328 307
328 285 291 295 310 318 318 320 333 321 323 324 327
Use five classes.
a) Find the class width.
(b) Make a frequency table showing class limits, class boundaries,
midpoints, frequencies, relative frequencies, and cumulative frequencies.
(c) Draw a histogram.
(d) Draw a relative-frequency histogram.
(e) Categorize the basic distribution shape as uniform, mound-shaped
sym-
metrical, bimodal, skewed left, or skewed right.
(f) Draw an ogive. Answer: 2.1.15
, ⩥ Certain kinds of tumors tend to recur. The following data represent the
lengths of time, in months, for a tumor to recur after chemotherapy. Use
five classes.
19 18 50 1 14 45 38 40 27
20 17 1 21 22 54 46 25 49
59 39 43 39 5 9 38 18 54
59 46 50 29 12 19 36 43
41 10 50 41 25 19 39
a) Find the class width.
(b) Make a frequency table showing class limits, class boundaries,
midpoints, frequencies, relative frequencies, and cumulative frequencies.
(c) Draw a histogram.
(d) Draw a relative-frequency histogram.
(e) Categorize the basic distribution shape as uniform, mound-shaped
sym-
metrical, bimodal, skewed left, or skewed right.
(f) Draw an ogive. Answer: 2.1.17
⩥ It is costly in both time and money to go to college. Does it pay off?
According to the Bureau of the Census, the answer is yes. The average
annual income (in thousands of dollars) of a household headed by a
person with the stated education level is as follows: 21.6 if ninth grade is
the high- est level achieved, 39.6 for high school graduates, 56.8 for
