Please help
in Statistics Answers by

Your answer

Your name to display (optional):
Privacy: Your email address will only be used for sending these notifications.
Anti-spam verification:
To avoid this verification in future, please log in or register.

1 Answer

Two separate sets: 9 “good” TVs and 3 “bad” TVs make up 12 TV sets.

The 5 TVs delivered to the hotel must consist of at least 2 bad TVs. So that could be 3 bad TVs and 2 good ones; or 3 good TVs and 2 bad ones.

There is only one way to get 3 bad TVs, because there are only 3 of them anyway. But there are 9×8/2=36 ways of getting 2 good TVs out of 9.

There are 3 ways of getting 2 bad TVs out of 3, and 9×8×7/(2×3)=84 ways of getting 3 good TVs out of 9. Combine these combinations: 3×84=252.

Add these combinations together (2 bad/3 good+2 good/3 bad): 252+36=288 ways of getting at least 2 defective TVs.

(If this were to be converted to a probability, we’d divide 288 by the number of ways 5 TVs could be selected out of 12, 288/792=4/11.)

by Top Rated User (646k points)

Related questions

1 answer
asked Jan 20, 2013 in Word Problem Answers by treena Level 1 User (740 points) | 368 views
1 answer
Welcome to MathHomeworkAnswers.org, where students, teachers and math enthusiasts can ask and answer any math question. Get help and answers to any math problem including algebra, trigonometry, geometry, calculus, trigonometry, fractions, solving expression, simplifying expressions and more. Get answers to math questions. Help is always 100% free!
82,951 questions
87,618 answers
1,966 comments
4,312 users