Probability - binomial ( I think)

[fabio.cborges]

Hi guys, I'm new here, from the last two days I am trying to solve this exercise. It seems super simple, but I can not find examples, anyone knows how to solve or any tips on how I can start.

>> 20% of students in a college study business. If 5 students are chosen at random what is the probability that:

(i) Exactly 1 will be a business studies student.
(ii) Less than 2 will be business studies students.

>> A firm submits tenders for two different contracts. The probability that the first tender will be successful is 70% and the probability that the second tender will be successful is 40%. Calculate the probability that:

(i) Neither will be successful.
(ii) Both will be successful.
(iii) At least one will be successful.

 

[Dr.Peterson]

The first is a binomial distribution problem. It will help us a lot if you show an attempt at applying that method, so we can see what you know and where you are making a mistake.

The second is not binomial. Just define events A = first is successful, B = second is successful, and find P(A not successful and B not successful), and P(A successful and B successful). Again, show, whatever you can do, or at least tell us what you have learned about "not" and "and" probabilities.

Showing work helps us know where we can start, and where to focus our attention.

 

[fabio.cborges]

Thanks so much for the answer, I have no attempts because I didn't know what the problem was, now that I know this is 'binomial distribution problem' I will try and post here later. I'm two days trying to figure out where to start ... Thanks for the tip

 

[fabio.cborges]

The first is a binomial distribution problem. It will help us a lot if you show an attempt at applying that method, so we can see what you know and where you are making a mistake.

The second is not binomial. Just define events A = first is successful, B = second is successful, and find P(A not successful and B not successful), and P(A successful and B successful). Again, show, whatever you can do, or at least tell us what you have learned about "not" and "and" probabilities.

Showing work helps us know where we can start, and where to focus our attention.

Thanks so much for the answer, I have no attempts because I didn't know what the problem was, now that I know this is 'binomial distribution problem' I will try and post here later. I'm two days trying to figure out where to start ... Thanks for the tip