Lesson: General Probability Strategies

Comment on General Probability Strategies

Does independent events always mutually exclusive and vice versa?
greenlight-admin's picture

If events A and B are possible (that is P(A) > 0 and P(B) > 0), then the two events cannot be both independent and mutually exclusive.

Awesome summary.. Loving it. thanks a ton!! Brent sir.
greenlight-admin's picture

Thanks Deepak!

For the additional practice question listed below I don't understand why we need to place B twice on the circle and why is is not just the circumference minus one of the triangles since there is a chord of 6 inches already
greenlight-admin's picture

Question link: https://gre.myprepclub.com/forum/if-two-points-a-and-b-are-randomly-plac...

Good question.

We went to find P(length of chord AB is at least 6 inches)

So, if we place point B to the LEFT of point A, then the resulting chord must have a length greater than (or equal to) 6.

Also, if we place point B to the RIGHT of point A, then the resulting chord must have a length greater than (or equal to) 6.

If we don't consider point B on EITHER side of point A, then we are not considering all possible cases (since point B can be placed either to the left or right of point A).

Does that help?


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