SOLUTION: A box contains 10 light bulbs, two of which are defective. Three bulbs are selected from the box. What is the probability that at least one bulb is good? Please help, thank you.

Question 265869: A box contains 10 light bulbs, two of which are defective. Three bulbs are selected from the box. What is the probability that at least one bulb is good? Please help, thank you.
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
A box contains 10 light bulbs, two of which are defective. Three bulbs are selected from the box. What is the probability that at least one bulb is good?
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P(>= 1 good) = 1 - P(none good)
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P(no good when drawing three would be 2C3/10C3
Then prob of at least one defective would be
1 - 2C3/10C3
But 2C3 doesn't exist or is zero
So P(at least one defective) would be 1-0 = 1
Or 100%.
Cheers,
Stan H.

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