Question 462364
P(a)=40/(30+10+70)=4/11
P(b)=80/110=8/11
P(a|b)=10/80=1/8 Note: The "|" mark is on most computer keyboards. On mine it is above the "\" next to the square and curly brackets.
P(b|a)=10/40=1/4
I am not familiar with what n(a) and n(b) mean.
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Ed