# More Binomial Prob

• Apr 17th 2010, 05:49 PM
dwsmith
More Binomial Prob
A fertility clinic claims to have a procedure for selecting the gender of a child. Among nine randomly selected couples who wished to have girls, seven got the intended result. Test a hypothesis to determine if the procedure does better than chance.

The answer is .0898; however, I obtained \$\displaystyle 9C7*.5^7*.5^2=.0703125\$.

What is the issue here?
• Apr 17th 2010, 05:52 PM
Debsta
Quote:

Originally Posted by dwsmith
A fertility clinic claims to have a procedure for selecting the gender of a child. Among nine randomly selected couples who wished to have girls, seven got the intended result. Test a hypothesis to determine if the procedure does better than chance.

The answer is .0898; however, I obtained \$\displaystyle 9C7*.5^7*.5^2=.0703125\$.

What is the issue here?

The answer to what is 0.0898??
• Apr 17th 2010, 06:00 PM
dwsmith
• Apr 17th 2010, 06:05 PM
Debsta
Quote:

Originally Posted by dwsmith

There is no "question" - you are testing a hypothesis.
• Apr 17th 2010, 06:07 PM
dwsmith
Yes, I understand that. The probability of having a boy and girl is 50%.

So I used the binomial procedure.
• Apr 17th 2010, 06:14 PM
Debsta
Quote:

Originally Posted by dwsmith
Yes, I understand that. The probability of having a boy and girl is 50%.

So I used the binomial procedure.

OK I get where the 0.07 came from just not sure where you got the 0.08 figure from
• Apr 17th 2010, 06:16 PM
dwsmith
• Apr 17th 2010, 06:18 PM
Debsta
Quote:

Originally Posted by dwsmith

Is the question that you posted word for word from your book. If it is then their "answer" doesn't make a lot of sense????
• Apr 17th 2010, 06:19 PM
dwsmith
Word for word my friend.
• Apr 17th 2010, 06:23 PM
Debsta
Quote:

Originally Posted by dwsmith
Word for word my friend.

How can the "answer" to "Test a hypothesis to determine if the procedure does better than chance" be a number???
Suggestion: Toss the book.(Thinking)
• Apr 17th 2010, 06:24 PM
dwsmith
Trust me, I know the book is garbage.