38 statistic questions

there is no 11&13 so it is gonna be 38 questions. if you have any question, please let me know
exam3.docx

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QUESTION 1
1. Using the standard normal distribution table, compute P(Z=1.87)
2. .4938
.0603
.0013
.0307
QUESTION 2
1. Using the standard normal distribution table, compute P(Z=2.5)
.9599
.9938
.8750
.3653
QUESTION 3
1.
Using the standard normal distribution table, compute P(-1.5Z=1.8)
2.
.0309
.0476
.8973
.5637
QUESTION 4
1. Given that X ~N(µ=10,s=5) compute P(X=15)
.3413
.1587
.2456
.5713
QUESTION 5
1. Given that X ~N(µ=10,s=5) compute P(10=Z=17)
.2742
.4368
.4332
.4192
QUESTION 6
1. Given that X ~N(µ=10,s=5) compute P(X=10)
.5
,347
.000
.208
QUESTION 7
1. Scores of the first test in ECON 261 follow a normal distribution with mean 70 and
standard deviation 5. Compute P(X=60).
.0228
.9772
.9862
.1325
QUESTION 8
1. Scores of the first test in ECON 261 follow a normal distribution with mean 70 and
standard deviation 5. Compute P(X<85). .9482 ,6343 ,4987 ,9987 QUESTION 9 1. Scores of the first test in ECON 261 follow a normal distribution with mean 70 and standard deviation 5. Compute P(65Z0)=.025 2.57 1.96 1.64 1.87 QUESTION 14 1. Using a normal distribution table, find Z0 such that: P(Z<-Z0) = .9868 1.96 -1.64 -2.22 2.17 QUESTION 15 1. The random sample X is normally distributed with mean 40 and standard deviation of 16. If n = 256, compute: P(x¯>42)
.4938
.4772
.0062
.0228
QUESTION 16
1. The random sample X is normally distributed with mean 40 and standard deviation
of 16. If n = 256, compute: P(3738)
.5080
.4772
.9772
.6038
QUESTION 18
1. A sample of n = 400 observations is drawn from a population with mean of 1000 ( µ =
1000) and standard deviation of 400 ( s = 400 ). Find P(x¯<1030). .9332 .3896 .9772 .8405 QUESTION 19 1. A sample of n = 400 observations is drawn from a population with mean of 1000 ( µ = 1000) and standard deviation of 400 ( s = 400 ). Find P(9601060). .0567 .4356 .0023 .0013 QUESTION 21 1. Random samples of size 1600 are taken from a population whose mean is 120 ( µ = 120 ) and standard deviation is 40 ( s = 40 ). The mean and the standard error of x¯ (sample mean) are respectively ... (120,2) (40,120) (120,1) (180,102) QUESTION 22 1. In the construction of a confidence interval for a population mean, if all else constant, an increase in the sample size will produce an interval that is ... Unchanged Narrower Wider Taller QUESTION 23 1. The standard deviation of x¯ is called The standard deviation of X The standard deviation of the population The standard error of X The mean deviation of X QUESTION 24 1. The Z-value associated with a 98% confidence interval is ... 2.33 or 2.34 3.84 or 3.8 2.57 or 2.58 1.28 or 1.27 QUESTION 25 1. The z-value associated with a 95% confidence interval is ... 1.83 1.96 1.94 2.22 QUESTION 26 1. The entire group of persons, places, or items that we want to collect observations from is known as ... Frame Sample Population Sample Space QUESTION 27 1. A sample wherein all items in a population have the same chance of being selected for inclusion in the sample is a ... Population sample Cluster sample Random sample Good sample QUESTION 28 1. A sampling distribution of the sample statistic x¯ is a ... Random sampling ox¯ Population sampling of x¯ Population distribution of x¯ Probability distribution of x¯ QUESTION 29 1. x¯ = 30 s=9 n = 100 The 90% confidence interval for µ is ... (18.325,31.642) (28.041, 21.965) (27.841, 36.457) (28.524, 31.476) QUESTION 30 1. 2. x¯ = 30 s=9 n = 100 The 95% confidence interval for µ is ... (28.043, 31.962) (27.681, 22.474) (28.236, 31.764) (28.674, 32.870) QUESTION 31 1. 2. x¯ = 30 s=9 n = 100 The 95% confidence interval for µ is ... (27.687, 32.313) (27.912, 32.109) (18.651, 31.972 ) (28.617, 32.326 ) QUESTION 32 1. Given =20, s =5 and n=25, construct the following confidence interval for µ: 90% confidence interval (18.16, 22.65) (23.24, 26.73) (18.36, 21.64 ) (22.45, 26.09) QUESTION 33 1. Given =20, s =5 and n=25, construct the following confidence intervals for µ: 95% CI (17.93, 22.06) (18.04, 21.96) (23.69, 26.34) (20.54, 25.48) QUESTION 34 1. Given =20, s =5 and n=25, construct the following confidence intervals ... The 99% confidence interval for µ is: (17.66, 27.04) (18.53, 24.94) (21.08, 27.87) (17.43, 22.57) QUESTION 35 1. Given a population with three observations: 2, 4, and 6 ... The population mean µ of the observations is: 2 3 4 6 QUESTION 36 1. Given a population with three observations: 2, 4, and 6 ... The population variance, Var(X)=s2 of the observations is: 4/3 2/3 1/3 8/3 QUESTION 37 1. Given a population with three observations: 2, 4, and 6 ... If a sample of n=2 data set is selected from this population of data, the mean of the sampling distribution of x¯, that is E(x¯) is 7 4 3 6 QUESTION 38 1. Given a population with three observations: 2, 4, and 6 ... If a sample of n=2 data set is selected from this population of data, the variance of the sampling distribution of x¯, that is Var(x¯) is 4/3 2/3 1/3 8/3 QUESTION 39 1. As the sample size n increases, the sampling error ... Increases Decreases Remains unchanged Converges to infinity QUESTION 40 1. The closer the sample mean is to the population mean ... The larger the sampling error The sample error is zero The smaller the sampling error The sampling error is infinite ... Purchase answer to see full attachment