SOLUTION: a jury is made up of 2 males and 8 females. Two jurors are selected at random for a follow up interview. Find the probability that both are males

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Question 330678: a jury is made up of 2 males and 8 females. Two jurors are selected at random for a follow up interview. Find the probability that both are males
Found 2 solutions by solver91311, jrfrunner:
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


The probability of successes in trials where is the probability of success on any given trial is given by:



Where is the number of combinations of things taken at a time and is calculated by

You need 2 successes in 2 trials where the probability of success on one trial is .



Which looks like a bunch of nasty arithmetic until you consider that:



and



So:




John

My calculator said it, I believe it, that settles it

Answer by jrfrunner(365) About Me  (Show Source):
You can put this solution on YOUR website!
choosing a male first and then choosing a second male are not independent events so......
probability that both are males =P(MM) =P(M first)*P(M second/M first)=2/10*1/9 = 2/90=0.022
first there are 2/10 chance of choosing a male, but once this male is selected the pool is reduced to 1 male in 9 jurors