Lab 3 - 1. True Margin of error is E=z * 0 over √ ❑ as n...

1. True, Margin of error is E=z * 0 over √
❑
as n increases e decreases
2. True because E = z * o over √
❑
To determine the sample size you need to estimate
the parameter, you must know the margin of error.
3. False The null hypothesis has an equality sign. Alternative is opposite to null. It have
≠, > , < signs
4. False If p value is less than
δ ,the nullhypothesisisrejected.
5. True The confidence interval can be used to test or claim a hypothesis.
2. za / 2 o over √ ❑
a=1 - c = 1 - 0.90= 0.10 o/2 = 0.20/2 =0.05
a/2 = 1.645 x - a/2 o over √
❑
121.60 - 1.645 6.36 over √
❑
121.60 - 1.7437 < u < 121.60 + 1.7437
119.8563 < u < 123.3437
The 90% confidence interval for true mean is ( 119.8563, 123.3437)
3. 93 + 83+ 76+ 92+77 + 81 + 78 +100 + 78 + 76 +75 over 11
= 909 over 11 = 82.6364
√
❑
[
x ¿
2
2 − ¿
Σ x
¿
over n
= √
❑
[ 75837 - 909 ^2 over 10
= √
❑
The value of true mean with 95% confidence
82.6346 0.025 x 8.4885 over √ ❑
82.6346 + 1.96 x 8.4885 over √
❑
(77.62, 8765)
4. N * p = 1500 * 0.42 =630
= √
❑
confidence interval = ( X-Z * s/ √
❑
(630 - 1.96 * 19.12/ √
❑
= (629.0324 , 630.9676)

5. Confidence level is 95% x= 1- 0.95= 0.05
Critical value 2/2 =196
n= pq ( 2/2 over E)