Question 1192045
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Answers:
a) 1/2
b) 1/2
c) 3/95 of getting two black; 100% of getting two non-green



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Explanation:


Part (a)


There are 10 red out of 20 total.


Therefore, 10/20 = 1/2 is the probability of selecting red. It happens half the time.


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Part (b)


We get the same answer as part (a) because there are 6 blue + 4 black = 10 that are either blue or black. 


This leads to 10/20 = 1/2 like before. 


Half of the balls are red, the other half are either blue or black.


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Part (c)


I'll assume non-replacement is happening here. Meaning that whatever is selected is not put back.


4 black, 20 total
4/20 = 1/5 = probability of selecting one black
3/19 = probability of selecting another black
Note the numerator and denominator subtracted by 1.


(4/20)*(3/19) = 12/380 = 3/95 is the probability of selecting 2 black in a row, assuming non replacement.


The probability of getting two non-green is 100% because there are no green balls in the box. The only colors we have are red, blue, and black.
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