Ten bulbs are drawn successively with replacement from a lot containing 10% defective bulbs. The probability that there is at least one defective bulb is :
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → $1-(9^{10}/10^{10})$
P(atleast one defective bulb) = 1 - P(no defective bulb)
$=1-{^{10}C}_0×(100\%-10\%)^{10}$
$=1-(\frac{9}{10})^{10}$