SOLUTION: A technician is launching fireworks near the end of a show. Of the remaining twelve fireworks, six are blue and six are red. If she launches 5 of them in a random order, what is

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Question 1140546: A technician is launching fireworks near the end of a show. Of the remaining twelve fireworks, six are blue and six are red. If she launches 5 of them in a random order, what is the probability that at least two of them are blue ones?
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
12C5 are the number of choices of 5 from 12
look at 1 or 0 are blue, and take the complement of that.
for 1: 6C1*6C4=6*15=90 possibilities
for 0: 6C5 or 6 ways
96 possibilities from 792=0.1212 probability they won't be or 0.8787 probability at least two are blue.
check
2 blue are 6C2*6C3=15*20=300
3 blue are 6C3*6C2=also 300
4 blue are 6C4*6C1=90
5 blue are 6 ways
And those are the other 696 possibilities.
696/792=0.8787 ANSWER