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Showing 2 events are independent, help needed

Shown in this link, I don't understand question 2ii about how to show the 2 events are not independent.

http://www.mei.org.uk/files/papers/2011_Jan_s1.pdf

I know so far that the probability of getting an even score on a 4 sided dice is 0.5 and the probability of getting a score less than 10 when two dice are thrown and their scores multiplied together is 13/16, I have to show the 2 events are not independent.

Isn't the formula P(A) x P(B) = P(AnB) for independent events because I end up with 0.5 x 13/16 = (0.5 x 13/16) which is 0.40625 = 0.40625 showing they ARE independent... What do I do?
(edited 11 years ago)
Reply 1
If A and B are independent then P(AB)=P(A)P(B)P(A\cap B)=P(A)P(B) and P(A)=P(AB)P(A)=P(A|B).
Reply 2
The question says show that they are not independent.

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