Statistics
posted by Help Please! .
A clinical trial tests a method designed to increase the probability of conceiving a girl. In the study, 449 babies were born, and 250 of them were girls. Use the sample data with .01 significance level to test the claim that with this method, the probability of a baby being a girl is greater than 0.5.
a.) What is the hypothesis test to be conducted?
b.) What is the test statistic? Z=? (round to 2 decimal places)
c.) What is the Pvalue? (round to 4 decimal places)
d.) What is the conclusion?
e.) Does the method appear to be effective?
Which formulas do i need?

a. Ho: p = 0.5
Ha: p > 0.5
b) z = 2.41
c) pvalue = 0.0080
d) reject the Ho; there is sufficient evidence to claim that the probability of a baby being a girl is greater than 0.5