UNSW Sem 2 Finals Thread (1 Viewer)

seanieg89

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Have you done rank and nullity of a matrix yet?

Another one is probability that would be alright for even a HSC student to do but I suck at probability unless it involves integration of some sort.

Here's the harder probability:

We roll a die successively, until we roll six consecutive sixes, in which case we stop rolling the die.
a) What is the probability we stop rolling it after the 13th throw?
b) What is the probability that we roll the die at least ten times?

Do that in 7 minutes max to be on time with the rest of the question/paper.
a) The last 6 rolls must be 6's. The 7-th roll must be a 1-5 (else we would have an earlier termination) The first 6 rolls can be anything as long as they aren't 6 consecutive 6's.

So

b) Take the complement, probability of termination on 7th,8th,9th rolls are all ((1/6)^6)(5/6) as the first rolls can't hurt us. So

 

4025808

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GG fucked up petroleum economics. Did okay in reservoir engineering.

Now to memorize a shit tonne of content for geology and petrophysics. Kill me now :(
 

JT145

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phone went off in my exam. lol
 

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