A group of researchers wants to estimate the true mean skidding distance along a new road in a certain forest. The skidding distances (in meters) were measured at 20 randomly selected road sites. These values are given in the accompanying table. Complete parts a through d.
490 |
348 |
455 |
199 |
290 |
405 |
570 |
439 |
545 |
385 |
|
299 |
435 |
183 |
261 |
275 |
402 |
311 |
313 |
141 |
426 |
a. Estimate the true mean skidding distance for the road with a 99% confidence interval.
(______,______) (Round to one decimal place as needed.)
b. Give a practical interpretation of the interval, part a. The confidence interval means that we are
______% confident that the true
▼
mean skidding distance
skidding distance standard deviation
skidding distance variance
for
▼
the sampled points
the whole road
is in the interval.
c. What conditions are required for the inference, part b, to be valid? Are these conditions reasonablysatisfied? Check all correct statements below.
A. The sample must be randomly selected from the population.
B. The sample size must be much smaller than the population size.
C. The population distribution must be approximately normal.
D. The sample must be selected carefully to represent the whole population.
Is it reasonable to assume that the population distribution is approximately normal?
A. No, because the sample distribution is definitely not normal.
B. Yes, because the sample distribution is approximately normal.
C. The condition does not apply.
Is it reasonable to assume that the sample is random?
A.The condition does not apply.
B.No, because we do not know the methods used by the researchers.
C.Yes, because the problem statement indicates that it is.
Is it reasonable to assume that the sample size is much smaller than the population size?
A.No, because the length of the road is unknown.
B. The condition does not apply.
C. Yes, because there are many points that could be chosen along the road. Is it reasonable to assume that the sample was selected carefully to represent the whole population?
A. Yes, because the problem statement indicates that it was.
B. No, because we do not know the methods used by the researchers.
C. The condition does not apply.
d. A logger working on the road claims the mean skidding distance is at least 450 meters. Do you agree?
▼
Yes
No
, because the value 450 lies
inside
outside
the confidence interval.
A group of researchers wants to estimate the true mean skidding distance along a new road...
A group of researchers wants to estimate the true mean skidding distance along a new road in a certain forest. The skidding distances (in meters) were measured at 20 randomly selected road sites. These values are given in the accompanying table. Complete parts a through d. 487 350 458 196 289 407 571 438 549 382 300 435 184 260 275 405 313 311 141 426 a. Estimate the true mean skidding distance for the road with a 95 %...
Q.4 A group of researchers wants to estimate the true mean skidding distance along a new road in a certain forest. The skidding distances? (in meters) were measured at 20 randomly selected road sites. These values are given in the accompanying table. Complete parts a through d. 485 351 459 199 288 408 574 439 546 385 298 430 184 263 272 403 310 312 141 426 a. Estimate the true mean skidding distance for the road with a 90?%...
A group of researchers wants to estimate the true mean skidding distance along a new road in a certain forest. The skidding distances (in meters) were measured at 20 randomly selected road sites. These values are given in the accompanying table. Complete parts a through d. 485 351 458 200 287 405 575 440 547 380 297 434 184 265 273 400 313 312 145 424 a. Estimate the true mean skidding distance for the road with a 95% confidence...
A group of researchers wants to estimate the true mean skidding distance along a new road in a certain forest. The skidding distances (in meters) were measured at 20 randomly selected road sites. These values are given in the accompanying table. Complete parts a through d. 485 351 458 200 287 405 575 440 547 380 297 434 184 265 273 400 313 312 145 424 a. Estimate the true mean skidding distance for the road with a 95% confidence...
A group of researchers wants to estimate the true mean skidding distance along a new road in a certain forest. The skidding distances (in meters) were measured at 20 randomly selected road sites. These values are given in the accompanying table. Complete parts a through d. 490 350 198 285 407 573 438 545 380 0 297 430 180 261 273 404 311 314 141 a. Estimate the true mean skidding distance for the road with a 99% confidence interval...
A group of researchers wants to estimate the true mean skidding distance along a new road in a certain forest. The skidding distances (in meters) were measured at 20 randomly selected road sites. These values are given in the accompanying table. Complete parts a through d 349 454 196 289 405 570 435 546 383 489 295 432 180 265 274 404 310310144 427 a Estmate the true mean skidding distance for the road with a 95% confidence interval D(Round...
This Quiz: 10 pts Question Heip A group of 20 randomly selected road sites. These values are given in the accompanying table. Complote parts a through d wants to estimate the true mean 489 349 459200 289 405 573 440 546 581 300 432 182 405 313 315 144 423 (Round to one decimal place as needed.) The confidence interval means that we are [1% confident that the true V for of 2 A. The sample must be randomly selected...
A group of researchers wants to estimate the true mean skidding dstance along a new road in a certain forest. The skidding distances (in meters) were measured at 20 randomly selected values are given in the accompanying table. Complete parts a through d 487 299 348 455 195 288 575 435 548 433180261 274 401314315142 85 423 a Estmate the true mean skidding distance for the road win a 90% cofdence i terval, (Round to one decimal place as needed)
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