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? 
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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.