Answer:
1/26
Step-by-step explanation:
There is only one 6 of hearts and only one ace of diamonds.
The probability of selecting the 6 of hearts is thus 1/52, and that of selecting the ace of diamonds is also 1/52.
The probability of selecting the 6 of hearts or the ace of diamonds is the SUM of these two results: 1/52 + 1/52 = 2/52 = 1/26.
Answer: The 95% confidence interval is approximately (55.57, 58.43)
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Explanation:
At 95% confidence, the z critical value is about z = 1.960 which you find using a table or a calculator.
The sample size is n = 17
The sample mean is xbar = 57
The population standard deviation is sigma = 3
The lower bound of the confidence interval is
L = xbar - z*sigma/sqrt(n)
L = 57 - 1.960*3/sqrt(17)
L = 55.5738905247863
L = 55.57
The upper bound is
U = xbar + z*sigma/sqrt(n)
U = 57 + 1.960*3/sqrt(17)
U = 58.4261094752137
U = 58.43
Therefore the confidence interval (L, U) turns into (55.57, 58.43) which is approximate.
I hope this picture helps. I'll elaborate if needed!
Answer:
The answer is "It would decrease, but not necessarily by 8%".
Step-by-step explanation:
They know that width of the confidence level is proportional to a confidence level. As just a result, reducing the confidence level decreases the width of a normal distribution, but not with the amount of variance in the confidence level. As just a result, when a person teaches a 90% standard deviation rather than a 98 percent normal distribution, the width of the duration narrows.
