Three friends, Rick, Brenda and Ali, go to a football match but forget to say which entrance
Question:
Three friends, Rick, Brenda and Ali, go to a football match but forget to say which entrance to the ground they will meet at. There are four entrances, A, B,C and D. Each friend chooses an entrance independently.
• The probability that Rick chooses entrance A is 1/3. The probabilities that he chooses entrances B,C or D are all equal.
• Brenda is equally likely to choose any of the four entrances.
• The probability that Ali chooses entrance C is 2/7 and the probability that he chooses entrance D is 3/5.
The probabilities that he chooses the other two entrances are equal.
i. Find the probability that at least 2 friends will choose entrance B.
ii. Find the probability that the three friends will all choose the same entrance.
Step by Step Answer:
Cambridge International AS & A Level Mathematics Probability & Statistics 1 Coursebook
ISBN: 9781108407304
1st Edition
Authors: Dean Chalmers, Julian Gilbey