part a)
Confidence Interval
X̅ ± t(α/2, n-1) S/√(n)
t(α/2, n-1) = t(0.05 /2, 100- 1 ) = 1.984
35.1 ± t(0.05/2, 100 -1) * 3.61/√(100)
Lower Limit = 35.1 - t(0.05/2, 100 -1) 3.61/√(100)
Lower Limit = 34.392
Upper Limit = 35.1 + t(0.05/2, 100 -1) 3.61/√(100)
Upper Limit = 35.808
95% Confidence interval is ( 34.392 , 35.808
)
Part b)
Confidence Interval
X̅ ± t(α/2, n-1) S/√(n)
t(α/2, n-1) = t(0.05 /2, 110- 1 ) = 1.982
53.2 ± t(0.05/2, 110 -1) * 3.36/√(110)
Lower Limit = 53.2 - t(0.05/2, 110 -1) 3.36/√(110)
Lower Limit = 52.572
Upper Limit = 53.2 + t(0.05/2, 110 -1) 3.36/√(110)
Upper Limit = 53.828
95% Confidence interval is ( 52.572 , 53.828
)
Part c)
Confidence Interval
X̅ ± t(α/2, n-1) S/√(n)
t(α/2, n-1) = t(0.05 /2, 115- 1 ) = 1.981
68.3 ± t(0.05/2, 115 -1) * 4.76/√(115)
Lower Limit = 68.3 - t(0.05/2, 115 -1) 4.76/√(115)
Lower Limit = 67.430
Upper Limit = 68.3 + t(0.05/2, 115 -1) 4.76/√(115)
Upper Limit = 69.170
95% Confidence interval is ( 67.430 , 69.170
)
Part d)
Confidence Interval
X̅ ± t(α/2, n-1) S/√(n)
t(α/2, n-1) = t(0.05 /2, 95- 1 ) = 1.986
41 ± t(0.05/2, 95 -1) * 2.81/√(95)
Lower Limit = 41 - t(0.05/2, 95 -1) 2.81/√(95)
Lower Limit = 40.435
Upper Limit = 41 + t(0.05/2, 95 -1) 2.81/√(95)
Upper Limit = 41.565
95% Confidence interval is ( 40.435 , 41.565
)
(1 point) A random sample of n measurements was selected from a population with unknown mean...
(1 point) A random sample of n measurements was selected from a population with unknown mean u and standard deviation o. Calculate a 99% confidence interval for u for each of the following situations: (a) n= 105, X = 25.8, s = = 2.92 sus (b) n = 95, x = 96, s = 4.13 su < (c) n = 85, X = 63.6, s = 2.31 su < (d) n = 115, x = 102.1, s = 2.95 su...
(1 point) A random sample of n measurements was selected from a population with unknown mean u and standard deviation o. Calculate a 90% confidence interval for p for each of the following situations: (a) n = 100 = 102.2, s = 2.28 << (b) n=90, Z = 84.8, s = 2.19 <u (c) n = 80, Z = 55.8, s 2.48 << (d) n=90, = 76.3, s = 2.68 Sus Note: You can earn partial credit on this problem.
A random sample of n measurements was selected from a population with unknown mean μ and standard deviation σ = 35 for each of the situations in parts a through d. Calculate a 99% confidence interval for μ for each of these situations. a. n = 75, x = 20 Interval: ( _____, _____ ) b. n = 150, x = 104 Interval: ( _____, _____ ) c. n = 90, x = 16 Interval: ( _____, _____ ) d....
and for 2. A random sample of n measurements is selected from a population with unknown mean known standard deviation o = 10. Calculate the width of a 95% confidence interval for these values of n: a. n=100 b. n=200 c. n=400 d. n=1000 e. n=2000
just got b wrong (1 point) A random sample of n measurements was selected from a population with unknown mean u and standard deviation o. Calculate a 90% confidence interval for u for each of the following situations: (a) n= m = 100, 7 100, = 102.2, s = 2.28 su < 101.825 102.575 (b) n = 90, z = 84.8, s = = 2.19 184.420 su < 185.180 (c) n 80, # 55.8, s = 2.48 su < 55.3444...
1. A random sample of n measurements was selected from a population with standard deviation σ=13.6 and unknown mean μ. Calculate a 90 % confidence interval for μ for each of the following situations: (a) n=45, x¯¯¯=89.8 ≤μ≤ (b) n=70, x¯¯¯=89.8 ≤μ≤ (c) n=100, x¯¯¯=89.8 ≤μ≤ (d) In general, we can say that for the same confidence level, increasing the sample size the margin of error (width) of the confidence interval. (Enter: ''DECREASES'', ''DOES NOT CHANGE'' or ''INCREASES'', without the...
a random sample of 11 items is drawn from a population whose standard deviation is unknown. The sample mean is x= 920 and the sample standard deviation is s = 25. Use Appendix D to find the values of Studengs t. a) Construct an interval estimate of u with 95% confidence. b) Construct an interval estimate of u with 95% confidence, assuming tha s=50. c) Construct an interval estimate of u with 95% confidence, assuming that s= 100 Round your...
If there is a recommended calculator or excel/ti-calculator formula please provide. Thanks! A random sample of n measurements was selected from a population with unknown mean u and standard deviation o = 15 for each of the situations in parts a through d. Calculate a 99% confidence interval for u for each of these situations. a. n=50, x=31 b. n=250, x= 112 c. n= 120, x = 16 d. n= 120, x=5.21 e. Is the assumption that the underlying population...
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