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

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%.

orchestra answered 2 years ago

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