The reading speed of second grade students in a large city is approximately normal, with a mean of 91 words per minute (wpm) and a standard deviation of 10 wpm. Complete parts (a) through (f). Click here to view the standard normal distribution table (page 1). Click here to view the standard normal distribution table (page 2). (d) What effect does increasing the sample size have on the probability? Provide an explanation for this result. A. Increasing the sample size decreases the probability because o, decreases as n increases.

Glencoe Algebra 1, Student Edition, 9780079039897, 0079039898, 2018
18th Edition
ISBN:9780079039897
Author:Carter
Publisher:Carter
Chapter10: Statistics
Section10.4: Distributions Of Data
Problem 19PFA
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Question
The reading speed of second grade students in a large city is approximately normal, with a mean of 91 words per minute (wpm) and a standard deviation of 10 wpm. Complete parts (a) through (f).
Click here to view the standard normal distribution table (page 1).
Click here to view the standard normal distribution table (page 2).
.....
(d) What effect does increasing the sample size have on the probability? Provide an explanation for this result.
A. Increasing the sample size decreases the probability because o, decreases as n increases.
B. Increasing the sample size increases the probability because o, increases as n increases.
C. Increasing the sample size decreases the probability because o, increases as n increases.
D. Increasing the sample size increases the probability because o, decreases as n increases.
(e) A teacher instituted a new reading program at school. After 10 weeks in the program, it was found that the mean reading speed of a random sample of 19 second grade students was 93.8 wpm. What might you conclude based on this result?
Select the correct choice below and fill in the answer boxes within your choice.
(Type integers or decimals rounded to four decimal places as needed.)
O A. A mean reading rate of 93.8 wpm is not unusual since the probability of obtaining a result of 93.8 wpm or more is
This means that we would expect a mean reading rate of 93.8 or higher from a population whose mean reading rate is
91 in
of
every 100 random samples of size n = 19 students. The new program is not abundantly more effective than the old program.
O B. A mean reading rate of 93.8 wpm is unusual since the probability of obtaining a result of 93.8 wpm or more is
. This means that we would expect a mean reading rate of 93.8 or higher from a population whose mean reading rate is 91
in
of every 100 random samples of size n = 19 students. The new program is abundantly more effective than the old program.
Transcribed Image Text:The reading speed of second grade students in a large city is approximately normal, with a mean of 91 words per minute (wpm) and a standard deviation of 10 wpm. Complete parts (a) through (f). Click here to view the standard normal distribution table (page 1). Click here to view the standard normal distribution table (page 2). ..... (d) What effect does increasing the sample size have on the probability? Provide an explanation for this result. A. Increasing the sample size decreases the probability because o, decreases as n increases. B. Increasing the sample size increases the probability because o, increases as n increases. C. Increasing the sample size decreases the probability because o, increases as n increases. D. Increasing the sample size increases the probability because o, decreases as n increases. (e) A teacher instituted a new reading program at school. After 10 weeks in the program, it was found that the mean reading speed of a random sample of 19 second grade students was 93.8 wpm. What might you conclude based on this result? Select the correct choice below and fill in the answer boxes within your choice. (Type integers or decimals rounded to four decimal places as needed.) O A. A mean reading rate of 93.8 wpm is not unusual since the probability of obtaining a result of 93.8 wpm or more is This means that we would expect a mean reading rate of 93.8 or higher from a population whose mean reading rate is 91 in of every 100 random samples of size n = 19 students. The new program is not abundantly more effective than the old program. O B. A mean reading rate of 93.8 wpm is unusual since the probability of obtaining a result of 93.8 wpm or more is . This means that we would expect a mean reading rate of 93.8 or higher from a population whose mean reading rate is 91 in of every 100 random samples of size n = 19 students. The new program is abundantly more effective than the old program.
Standard normal distribution table (page 1)
Standard normal distribution table (page 2)
Area
Area
Standard Normal Distribution
Standard Normal Distribution
0.00
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.00
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.0003
0.0004
0.0006
0.0009
0.0012
0.0003
0.0004
0.0006
-3.4
-3.3
-3.2
0.0003
0.0005
0.0003
0.0005
0.0007
0.0003
0.0005
0.0006
0.5199
0.5596
0.5987
0.5319
0.5714
0.6103
0.0003
0.0003
0.0004
0.0006
0.0003
0.0004
0.0006
0.0003
0.0004
0.0005
0.0002
0.0003
0.0005
0.0007
0.0010
0.5000
0.5398
0.5793
0.6179
0.6554
0.5040
0.5438
0.5832
0.5080
0.5478
0.5871
0.6255
0.6628
0.5120
0.5517
0.5910
0.5160
0.5557
0.5948
0.5239
0.5636
0.6026
0.6406
0.6772
0.5279
0.5675
0.6064
0.5359
0.5753
0.6141
0.6517
0.0
0.0004
0.0005
0.0008
0.0011
0.1
0.2
0.0007
0.0009
0.0013
0.0008
0.0011
0.6217
0.6591
0.6331
0.6700
0.6368
0.6736
0.6443
0.6808
-3.1
0.6480
0.0010
0.0013
0.0009
0.0013
0.0008
0.0012
0.0008
0.0007
0.0010
0.3
0.6293
0.6664
-3.0
0.0011
0.4
0.6844
0.6879
-29
-28
-2.7
0.0019
0.0026
0.0035
0.0017
0.0023
0.0032
0.0016
0.0022
0.0030
0.0040
0.0054
0.0015
0.0021
0.0029
0.0039
0.0052
0.0015
0.0021
0.0028
0.0014
0.0020
0.0027
0.0014
0.0019
0.0026
0.6915
0.7257
0.7580
0.6985
0.7324
0.7642
0.7939
0.8212
0.7019
0.7357
0.7673
0.7123
0.7454
0.7764
0.8051
0.8315
0.7157
0.0018
0.0025
0.0034
0.0018
0.0024
0.0033
0.0016
0.0023
0.0031
0.7224
0.7549
0.7852
0.5
0.6950
0.7291
0.7611
0.7054
0.7389
0.7704
0.7088
0.7422
0.7734
0.7486
0.7794
0.7190
0.7517
0.7823
0.6
0.7
-2.6
-2.5
0.0047
0.0062
0.0045
0.0060
0.0044
0.0059
0.0038
0.0051
0.7881
0.8159
0.7967
0.8238
0.8023
0.8289
0.8133
0.8389
0.0043
0.0041
0.0037
0.0049
0.0036
0.0048
0.8
0.7910
0.8186
0.7995
0.8264
0.8078
0.8106
0.8365
0.0057
0.0055
0.9
0.8340
0.0080
0.0104
0.0136
0.0174
0.0222
0.0078
0.0102
0.0132
0.0170
0.0217
-2.4
-2.3
-2.2
0.0082
0.0107
0.0139
0.0075
0.0099
0.0073
0.0096
0.0125
0.0071
0.0094
0.0122
0.0069
0.0091
0.0119
0.0068
0.0089
0.0116
0.0064
0.0084
0.0110
0.8413
0.8643
0.8849
0.8438
0.8665
0.8485
0.8708
0.8907
0.8508
0.8729
0.8925
0.8599
0.8810
0.8997
0.8461
0.0066
0.0087
0.0113
1.0
1.1
1.2
0.8531
0.8749
0.8944
0.8554
0.8770
0.8962
0.8577
0.8790
0.8980
0.8621
0.8830
0.90 15
0.8686
0.8888
0.9066
0.9222
0.0129
0.8869
-2.1
-2.0
0.0179
0.0228
0.0166
0.0212
0.0162
0.0207
0.0158
0.0202
0.0154
0.0197
0.0150
0.0192
0.0146
0.0188
0.0143
0.0183
1.3
1.4
0.9032
0.9192
0.9082
0.9236
0.9115
0.9265
0.9049
0.9099
0.9251
0.9131
0.9147
0.9292
0.9162
0.9306
0.9177
0.9207
0.9279
0.9319
0.0287
0.0359
0.0446
0.0268
0.0336
0.0418
0.0256
0.0322
0.0401
0.0250
0.0314
0.0392
0.0239
0.0301
0.0375
0.0465
0.0571
1.5
1.6
1.7
1.8
1.9
0.9357
0.9474
0.9573
0.9656
0.9726
-1.9
-1.8
-1.7
-1.6
0.0281
0.0351
0.0436
0.0274
0.0344
0.0427
0.0262
0.0329
0.0409
0.0505
0.0618
0.0244
0.0307
0.0384
0.0233
0.0294
0.0367
0.9332
0.9452
0.9554
0.9345
0.9463
0.9564
0.9370
0.9484
0.9582
0.9382
0.9495
0.9591
0.9394
0.9505
0.9599
0.9406
0.9515
0.9418
0.9525
0.9616
0.9429
0.9535
0.9625
0.9441
0.9545
0.9633
0.9706
0.9608
0.0548
0.0668
0.0537
0.0655
0.0526
0.0643
0.0495
0.0606
0.9641
0.9713
0.0516
0.0485
0.0594
0.0475
0.0582
0.0455
0.0559
0.9649
0.9719
0.9693
0.9756
0.9664
0.9671
0.9738
0.9678
0.9744
0.9686
0.9699
0.9761
-1.5
0.0630
0.9732
0.9750
0.9767
-14
-13
-1.2
0.0793
0.0951
0.1131
0.1335
0.1562
0.0764
0.0918
0.1093
0.0749
0.0901
0.1075
0.1271
0.1492
0.0735
0.0885
0.1056
0.1251
0.1469
0.0721
0.0869
0.1038
0.0708
0.0853
0.1020
0.9772
0.9821
0.9861
0.9893
0.9918
0.9817
0.9857
0.9890
0.0808
0.0968
0.1151
0.0778
0.0934
0.0694
0.0838
0.1003
0.0681
0.0823
0.0985
2.0
2.1
0.9778
0.9826
0.9864
0.9783
0.9830
0.9868
0.9788
0.9834
0.9871
0.9793
0.9838
0.9875
0.9798
0.9842
0.9878
0.9803
0.9846
0.9881
0.9808
0.9850
0.9884
0.9812
0.9854
0.9887
0.1112
2.2
-1.1
-1.0
0.1357
0.1587
0.1210
0.1423
0.1190
0.1401
0.1170
0.1379
2.3
2.4
0.9906
0.9929
0.9916
0.9936
0.1314
0.1292
0.1515
0.1230
0.1446
0.9896
0.9898
0.9901
0.9925
0.9904
0.9909
0.9911
0.9913
0.1539
0.9920
0.9922
0.9927
0.9931
0.9932
0.9934
0.1841
0.2119
0.2420
0.1736
0.2005
0.2296
0.2611
0.1635
0.1894
0.2177
0.9938
0.9953
0.9965
0.9945
0.9959
0.9969
0.9946
0.9960
0.9970
-0.9
-08
0.1814
0.2090
0.2389
0.1788
0.2061
0.2358
0.1762
0.2033
0.2327
0.2643
0.1711
0.1977
0.2266
0.1685
0.1949
0.2236
0.1660
0.1922
0.2206
0.2514
0.1611
0.1867
0.2148
2.5
2.6
2.7
0.9940
0.9955
0.9966
0.9941
0.9956
0.9967
0.9943
0.9957
0.9968
0.9948
0.9961
0.9971
0.9949
0.9962
0.9972
0.0079
0.9951
0.9963
0.9973
0.9952
0.9964
0.9974
-0.7
-0.6
0.2743
0.2709
0.2676
0.2578
0.2546
0.2483
0.2451
2.8
0.0074
0.0075
0.0076
0.0077
0.0077
0.0078
0.0070
0.0080
0.0081
Transcribed Image Text:Standard normal distribution table (page 1) Standard normal distribution table (page 2) Area Area Standard Normal Distribution Standard Normal Distribution 0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.0003 0.0004 0.0006 0.0009 0.0012 0.0003 0.0004 0.0006 -3.4 -3.3 -3.2 0.0003 0.0005 0.0003 0.0005 0.0007 0.0003 0.0005 0.0006 0.5199 0.5596 0.5987 0.5319 0.5714 0.6103 0.0003 0.0003 0.0004 0.0006 0.0003 0.0004 0.0006 0.0003 0.0004 0.0005 0.0002 0.0003 0.0005 0.0007 0.0010 0.5000 0.5398 0.5793 0.6179 0.6554 0.5040 0.5438 0.5832 0.5080 0.5478 0.5871 0.6255 0.6628 0.5120 0.5517 0.5910 0.5160 0.5557 0.5948 0.5239 0.5636 0.6026 0.6406 0.6772 0.5279 0.5675 0.6064 0.5359 0.5753 0.6141 0.6517 0.0 0.0004 0.0005 0.0008 0.0011 0.1 0.2 0.0007 0.0009 0.0013 0.0008 0.0011 0.6217 0.6591 0.6331 0.6700 0.6368 0.6736 0.6443 0.6808 -3.1 0.6480 0.0010 0.0013 0.0009 0.0013 0.0008 0.0012 0.0008 0.0007 0.0010 0.3 0.6293 0.6664 -3.0 0.0011 0.4 0.6844 0.6879 -29 -28 -2.7 0.0019 0.0026 0.0035 0.0017 0.0023 0.0032 0.0016 0.0022 0.0030 0.0040 0.0054 0.0015 0.0021 0.0029 0.0039 0.0052 0.0015 0.0021 0.0028 0.0014 0.0020 0.0027 0.0014 0.0019 0.0026 0.6915 0.7257 0.7580 0.6985 0.7324 0.7642 0.7939 0.8212 0.7019 0.7357 0.7673 0.7123 0.7454 0.7764 0.8051 0.8315 0.7157 0.0018 0.0025 0.0034 0.0018 0.0024 0.0033 0.0016 0.0023 0.0031 0.7224 0.7549 0.7852 0.5 0.6950 0.7291 0.7611 0.7054 0.7389 0.7704 0.7088 0.7422 0.7734 0.7486 0.7794 0.7190 0.7517 0.7823 0.6 0.7 -2.6 -2.5 0.0047 0.0062 0.0045 0.0060 0.0044 0.0059 0.0038 0.0051 0.7881 0.8159 0.7967 0.8238 0.8023 0.8289 0.8133 0.8389 0.0043 0.0041 0.0037 0.0049 0.0036 0.0048 0.8 0.7910 0.8186 0.7995 0.8264 0.8078 0.8106 0.8365 0.0057 0.0055 0.9 0.8340 0.0080 0.0104 0.0136 0.0174 0.0222 0.0078 0.0102 0.0132 0.0170 0.0217 -2.4 -2.3 -2.2 0.0082 0.0107 0.0139 0.0075 0.0099 0.0073 0.0096 0.0125 0.0071 0.0094 0.0122 0.0069 0.0091 0.0119 0.0068 0.0089 0.0116 0.0064 0.0084 0.0110 0.8413 0.8643 0.8849 0.8438 0.8665 0.8485 0.8708 0.8907 0.8508 0.8729 0.8925 0.8599 0.8810 0.8997 0.8461 0.0066 0.0087 0.0113 1.0 1.1 1.2 0.8531 0.8749 0.8944 0.8554 0.8770 0.8962 0.8577 0.8790 0.8980 0.8621 0.8830 0.90 15 0.8686 0.8888 0.9066 0.9222 0.0129 0.8869 -2.1 -2.0 0.0179 0.0228 0.0166 0.0212 0.0162 0.0207 0.0158 0.0202 0.0154 0.0197 0.0150 0.0192 0.0146 0.0188 0.0143 0.0183 1.3 1.4 0.9032 0.9192 0.9082 0.9236 0.9115 0.9265 0.9049 0.9099 0.9251 0.9131 0.9147 0.9292 0.9162 0.9306 0.9177 0.9207 0.9279 0.9319 0.0287 0.0359 0.0446 0.0268 0.0336 0.0418 0.0256 0.0322 0.0401 0.0250 0.0314 0.0392 0.0239 0.0301 0.0375 0.0465 0.0571 1.5 1.6 1.7 1.8 1.9 0.9357 0.9474 0.9573 0.9656 0.9726 -1.9 -1.8 -1.7 -1.6 0.0281 0.0351 0.0436 0.0274 0.0344 0.0427 0.0262 0.0329 0.0409 0.0505 0.0618 0.0244 0.0307 0.0384 0.0233 0.0294 0.0367 0.9332 0.9452 0.9554 0.9345 0.9463 0.9564 0.9370 0.9484 0.9582 0.9382 0.9495 0.9591 0.9394 0.9505 0.9599 0.9406 0.9515 0.9418 0.9525 0.9616 0.9429 0.9535 0.9625 0.9441 0.9545 0.9633 0.9706 0.9608 0.0548 0.0668 0.0537 0.0655 0.0526 0.0643 0.0495 0.0606 0.9641 0.9713 0.0516 0.0485 0.0594 0.0475 0.0582 0.0455 0.0559 0.9649 0.9719 0.9693 0.9756 0.9664 0.9671 0.9738 0.9678 0.9744 0.9686 0.9699 0.9761 -1.5 0.0630 0.9732 0.9750 0.9767 -14 -13 -1.2 0.0793 0.0951 0.1131 0.1335 0.1562 0.0764 0.0918 0.1093 0.0749 0.0901 0.1075 0.1271 0.1492 0.0735 0.0885 0.1056 0.1251 0.1469 0.0721 0.0869 0.1038 0.0708 0.0853 0.1020 0.9772 0.9821 0.9861 0.9893 0.9918 0.9817 0.9857 0.9890 0.0808 0.0968 0.1151 0.0778 0.0934 0.0694 0.0838 0.1003 0.0681 0.0823 0.0985 2.0 2.1 0.9778 0.9826 0.9864 0.9783 0.9830 0.9868 0.9788 0.9834 0.9871 0.9793 0.9838 0.9875 0.9798 0.9842 0.9878 0.9803 0.9846 0.9881 0.9808 0.9850 0.9884 0.9812 0.9854 0.9887 0.1112 2.2 -1.1 -1.0 0.1357 0.1587 0.1210 0.1423 0.1190 0.1401 0.1170 0.1379 2.3 2.4 0.9906 0.9929 0.9916 0.9936 0.1314 0.1292 0.1515 0.1230 0.1446 0.9896 0.9898 0.9901 0.9925 0.9904 0.9909 0.9911 0.9913 0.1539 0.9920 0.9922 0.9927 0.9931 0.9932 0.9934 0.1841 0.2119 0.2420 0.1736 0.2005 0.2296 0.2611 0.1635 0.1894 0.2177 0.9938 0.9953 0.9965 0.9945 0.9959 0.9969 0.9946 0.9960 0.9970 -0.9 -08 0.1814 0.2090 0.2389 0.1788 0.2061 0.2358 0.1762 0.2033 0.2327 0.2643 0.1711 0.1977 0.2266 0.1685 0.1949 0.2236 0.1660 0.1922 0.2206 0.2514 0.1611 0.1867 0.2148 2.5 2.6 2.7 0.9940 0.9955 0.9966 0.9941 0.9956 0.9967 0.9943 0.9957 0.9968 0.9948 0.9961 0.9971 0.9949 0.9962 0.9972 0.0079 0.9951 0.9963 0.9973 0.9952 0.9964 0.9974 -0.7 -0.6 0.2743 0.2709 0.2676 0.2578 0.2546 0.2483 0.2451 2.8 0.0074 0.0075 0.0076 0.0077 0.0077 0.0078 0.0070 0.0080 0.0081
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