Question

In: Statistics and Probability

A researcher claims that 19% of US adults are smokers. In a random sample of 250...

A researcher claims that 19% of US adults are smokers. In a random sample of 250 US adults 55 were found to be smokers. Use a 0.05 significance level to test the researcher’s claim. please show step by step details

Solutions

Expert Solution

A researcher claims that 19% of US adults are smokers.

P:- proportion of US adults are smokers

we want to test that 19% of US adults are smokers.

The null & alternative hypothesis:

Ho: P = 0.19

vs'

Ha: P # 0.19

We may conclude that the there not enough evidence to support the claim that the population proportion of US adults were smokers is different from 19%.


Related Solutions

According to a recent study, 22.6% of adults are smokers. A random sample of 300 adults...
According to a recent study, 22.6% of adults are smokers. A random sample of 300 adults is obtained. Describe the sampling distribution of the sample proportion of adults who smoke. In a random sample of 300 adults, what is the probability that at least 50 are smokers? Would it be unusual if a random sample of 300 adults resulted in 17% or less being smokers?
22% of US adults use Twitter. A random sample of 15 US adults is selected. a)...
22% of US adults use Twitter. A random sample of 15 US adults is selected. a) Find the probability that the sample contains exactly 4 Twitter users. b) Find the probability that at least one US adult in the sample uses Twitter. c) Find the mean and standard deviation for the number of US adults using Twitter.
A random sample of 100 San Diego adults reveals 11 smokers. To test whether the prevalence...
A random sample of 100 San Diego adults reveals 11 smokers. To test whether the prevalence of smoking in San Diego is lower than national prevalence value of 0.21, compute the 95% C.I. of the population p using the San Diego random sample.
A medical researcher compares the pulse rates of smokers and nonsmokers. A sample of 71 smokers...
A medical researcher compares the pulse rates of smokers and nonsmokers. A sample of 71 smokers had a mean pulse rate of 81. A sample of 86 nonsmokers had a mean pulse rate of 77. Assume the standard deviation of the pulse rates is known to be 7 for smokers and 7 for non- smokers. Using these results, conduct a hypothesis test of the conjecture that the true mean pulse rate for smokers is different from the true mean pulse...
A medical researcher says that less than 24​%of adults in a certain country are smokers. In...
A medical researcher says that less than 24​%of adults in a certain country are smokers. In a random sample of 250 adults from that​ country,18.8​% say that they are smokers. At alphaαequals=0.05, is there enough evidence to support the​ researcher's claim? Complete parts​ (a) through​ (e) below.​(a) Identify the claim and stateUpperH0and Upper H Subscript aHa. What is the​ claim? A.Less than 24​%of all adults are smokers. B.Exactly 18.8​%of all adults are smokers. C.Exactly 18.8​% of adults in the country...
In a random sample of 1500 US adults, 780 of them are “Thriving” which is defined...
In a random sample of 1500 US adults, 780 of them are “Thriving” which is defined as rating their current life as 7 or higher on a 10-point scale and rating their future life as 8 or higher on a 10-point scale. Find and interpret a 99% confidence interval for the proportion of all US adults who are thriving (based on this definition.)
an education researcher claims that 54% of college students work year round. in a random sample...
an education researcher claims that 54% of college students work year round. in a random sample of 200 college students 108 say they work year round at alpha =0.10, is there enough evidence to reject the reseachers claim
An education researcher claims that 62% of college students work year round. in a random sample...
An education researcher claims that 62% of college students work year round. in a random sample of 200 college students, 124 say they work year round. At a =0.01. what is the critical values? what is standardized test statistic? Identify the P-value? reject or fail to reject?
An education researcher claims that 62% of college students work​ year-round. In a random sample of...
An education researcher claims that 62% of college students work​ year-round. In a random sample of 200 college​ students, 124 say they work​ year-round. At alpha equals=0.010​, is there enough evidence to reject the​ researcher's claim? A.) What is the critical value? B.) What is the rejection region? C.) What is the standardized test statistic z? D.) Should the null hypothesis be rejected?
in a random sample of 500 people aged 20-24, 110 were smokers. in a random sample...
in a random sample of 500 people aged 20-24, 110 were smokers. in a random sample of 450 people aged 25-29, 65 were smokers. test the claim that the proprtion of smokers age 20-24 is higher than the proportion of smokers age 25-29. use a significance level of 0.01. please show work!
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT