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# S1 watch

1. I travel to work by route A or route B. The probability that I choose route A is 1/4. The probability that I am late for work if I go via route A is 2/3 and the corresponding probability if I go via route
B is 1/3.
(a) What is the probability that I am late for work on Monday?
(b) Given that I am late for work, what is the probability that I went via route B?

i CANT do part b) the answer is 3/5 how??
2. (Original post by sciencenerdz)
I travel to work by route A or route B. The probability that I choose route A is 1/4. The probability that I am late for work if I go via route A is 2/3 and the corresponding probability if I go via route
B is 1/3.
(a) What is the probability that I am late for work on Monday?
(b) Given that I am late for work, what is the probability that I went via route B?

i CANT do part b) the answer is 3/5 how??
What comes to mind when it says 'given' in the question?
3. (Original post by SeanFM)
What comes to mind when it says 'given' in the question?
i donr know what equation to use
4. (Original post by sciencenerdz)
i donr know what equation to use
What if I shuffled the sentence around? Maybe that will help

What is the probability of going via route B given that I was late?

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Updated: March 20, 2016
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