1)
a)
P(at least one event) = 1 - P(neither event) = 1 -
3/8=5/8
b)
P(C u D) = 1 - P(C u D)' = 1 - 0.4=0.6
P(D) = P(C u D) - P( C ) + P(C n D) = 0.6-0.5+0.2 = 0.3
2)
a)
P(both marbles black)=4/10*3/9=2/15
b)
P(first red|second is black) = 6/10*4/9=4/15
Concept 8. When calculating a 95% confidence interval for a population mean, which is the most important situation where use of the t distribution would be better than use of the normal distribu...
mean is very close to the sample mediarn. that the waiting time is more than 30 days? Which sample, a or b, offers more compelling A. It is impossible to tell from the box plots. evidence B. The two sample offer about the same evidence C. Sample B D. Sample A Write the letter of each correct statement Concept 8, when calculating a 95% confidence interva important situation where use of the t distribution would be better distribution? for a...
When constructing a 95% confidence interval for a population mean μ, what is the most important condition that must be approximately satisfied so that in 95% of repeated samples the calculated intervals will cover the unknown value μ? A. The population standard deviation must always be small. B. The sample size n must be at least 100 (so that the Central Limit Theorem applies). C. The population from which the sample is drawn must be at least 10 times the...
The data of a major referral hospital showed that most patients with ischemic heart disease (IHD) were black American. Based on this, it was concluded that black Americans are at higher risk of IHD compared to other community groups. How would you describe the conclusion? A. Correct, because risk factors for IHD are more common in black African American. B. Incorrect, because no test of statistical significance has been made C. Incorrect, because prevalence is used instead of incidence D....
The data of a major referral hospital showed that most patients with ischemic heart disease (IHD) were black American. Based on this, it was concluded that black Americans are at higher risk of IHD compared to other community groups. How would you describe the conclusion? A. Correct, because risk factors for IHD are more common in black African American. B. Incorrect, because no test of statistical significance has been made C. Incorrect, because prevalence is used instead of incidence D....