Assume that different groups of couples use a particular method of gender select
ID: 3042781 • Letter: A
Question
Assume that different groups of couples use a particular method of gender selection and each couple gives birth to one baby. This method is designed to increase the likelihood that each baby will be a girl, but assume that the method has no effect, so the probability of a girl is 0.5. Assume that the groups consist of 16 couples. Complete parts (a) through (c) below.
a. Find the mean and the standard deviation for the numbers of girls in groups of 16 births. The value of the mean is equals=. (Type an integer or a decimal. Do not round.) The value of the standard deviation is equals= . (Round to one decimal place as needed.)
b. Use the range rule of thumb to find the values separating results that are significantly low or significantly high. Values of girls or fewer are significantly low. (Round to one decimal place as needed.) Values of girls or greater are significantly high. (Round to one decimal place as needed.)
c. Is the result of girls a result that is significantly high?
What does it suggest about the effectiveness of the method? The result significantly high, because girls is nothing girls. A result of girls would suggest that the method (Round to one decimal place as needed.)
Assume that different groups of couples use a particular method of gender selection and each couple gives birth to one baby. This method is designed to increase the likelihood that each baby will be a girl, but assume that the method has no effect, so the probability of a girl is 0.5. Assume that the groups consist of 16 couples. Complete parts (a) through (c) below.
a. Find the mean and the standard deviation for the numbers of girls in groups of 16 births. The value of the mean is equals=. (Type an integer or a decimal. Do not round.) The value of the standard deviation is equals= . (Round to one decimal place as needed.)
b. Use the range rule of thumb to find the values separating results that are significantly low or significantly high. Values of girls or fewer are significantly low. (Round to one decimal place as needed.) Values of girls or greater are significantly high. (Round to one decimal place as needed.)
c. Is the result of girls a result that is significantly high?
What does it suggest about the effectiveness of the method? The result significantly high, because girls is nothing girls. A result of girls would suggest that the method (Round to one decimal place as needed.)
Explanation / Answer
Solution
Given that n = 16 and p =0.5
(a) Mean = np = 16*0.5 = 8
Variance = np(1-p) = 16*0.5*0.5 = 4 , standard deviation = 2