SOLUTION: Please help me with this question. The Australian sheep dog is a breed renowned for its intelligence and work ethic. It is estimated that 40% of adult Australian sheep dogs weigh

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Question 1142268: Please help me with this question.
The Australian sheep dog is a breed renowned for its intelligence and work ethic. It is estimated that 40% of adult Australian sheep dogs weigh 65 pounds or more. A sample of 10 adult dogs is studied. What is the probability that more than 7 of them weigh 65 lb or more?
I understand that n=10 p=.4 and q=.6, however, I do not know what x is. I also do not know which formula to use to get the probability for this problem
Answer by ikleyn(52818) About Me  (Show Source):
You can put this solution on YOUR website!
.

If you take p= 0.4, q= 0.6,  then the solution is as follows.


    Probability(more than 7 of them weight 65 pounds or more) = P(8) + P(9) + P(10).


Further,


    P(8) = C%5B10%5D%5E8%2Ap%5E8%2Aq%5E2 = %28%2810%2A9%29%2F%281%2A2%29%29%2A0.4%5E8%2A0.6%5E2 = 0.010617;


    P(9) = C%5B10%5D%5E9%2Ap%5E9%2Aq%5E1 = 10%2A0.4%5E9%2A0.6       = 0.001573;


    P(10) = p%5E10           = 0.4%5E10       = 0.00105.


I leave it to you to add these numbers and to get the numerical value of the answer.


It is how such problems are to be solved.

In your post, you didn't explain what the "x" is, so I do not touch this issue.