SOLUTION: An urn contains four black balls and six white balls. What is the probability of getting one black and one white ball in two consecutive draws from the urn?

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Question 1040102: An urn contains four black balls and six white balls. What is the probability of getting one black and one white ball in two consecutive draws from the urn?
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
There are 4 possible outcomes,
BB
BW
WB
WW
Calculate the probabilities of each.
I wont simplify values until the end.
First with replacement,
P%28BB%29=%284%2F10%29%284%2F10%29=16%2F100
P%28BW%29=%284%2F10%29%286%2F10%29=24%2F100
P%28WB%29=%286%2F10%29%284%2F10%29=24%2F100
P%28WW%29=%286%2F10%29%286%2F10%29=36%2F100
So then,
P=24%2F100%2B24%2F100=48%2F100=12%2F25
.
.
.
Without replacement,
P%28BB%29=%284%2F10%29%283%2F9%29=12%2F90
P%28BW%29=%284%2F10%29%286%2F9%29=24%2F90
P%28WB%29=%286%2F10%29%284%2F9%29=24%2F90
P%28WW%29=%286%2F10%29%285%2F10%29=30%2F100
So then,
P=24%2F90%2B24%2F90=48%2F90=24%2F45