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sinclam2 / intro-to-probability-solutions

Solutions to the exercises in Grinstead and Snell's Introduction to Probability
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Your solution to 01.2.09 is incorrect #1

Open Brettkgamble opened 4 years ago

Brettkgamble commented 4 years ago

https://github.com/sinclam2/intro-to-probability-solutions/blob/master/01.2-discrete-probability-distributions/09-Solution.ipynb

I am new to Probability and was working through this solution and was having difficulty coming to the same answer that has been published in various places as a solution to the probability that a student chooses mathematics. Your example is incorrect where you state 5/8 + 5/8 - 1/4 = 10/8 - 5/8. I am not sure how you got the - 5/8 as it should be 1/4, in which case the answer should be 1.

P( Art ∪French)=P(art)+P(French)-P(art ∩French) P(art ∪French)=5/8+5/8-1/4 =10/8-2/8 =1

There is a high possibility that I am incorrect.....

wirekang commented 7 months ago

I'm quite sure that is incorrect, since there is no case to select two electives not containing art or French.