Question

Does second-hand smoke increase the risk of a low birthweight? A baby is considered have low birthweight if he/she weighs less than 5.5 pounds at birth. According to the National Center of Health Statistics, about 7.8% of all babies born in the U.S. are categorized as low birthweight.

Suspecting that the national percentage is higher than 7.8%, researchers randomly select 1200 babies whose mothers had extensive exposure to second-hand smoke during pregnancy and find that 10.4% of the sampled babies are categorized as low birth weight.

Let p be the proportion of all babies in the U.S. that are categorized as "low birth weight." Give the null and alternative hypotheses for this research question.

1. H ₀ : p = 0.078

   H _a : p ≠0.078

2. H ₀ : p = 0.078

   H _a : p > 0.078

3. H ₀ : p = 0.104

   H _a : p ≠0.104

4. H ₀ : μ = .078

   H _a : μ > .078

Answer 1

From the information, consider p is the proportion of all babies in the U. S. that are categorized as "low birth weight" Null hypothesis, Ho:p 0.078 Altemative hypothesis, H p>0.078