Practicing Success

Target Exam

CUET

Subject

-- Mathematics - Section A

Chapter

Probability

Question:

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 :

Options:

$1-(9^9/10^9)$

$9/10$

$1-(9^{10}/10^{10})$

$1-(10^{10}/9^{10})$

Correct Answer:

$1-(9^{10}/10^{10})$

Explanation:

The correct answer is Option (3) → $1-(9^{10}/10^{10})$

P(atleast one defective bulb) = 1 - P(no defective bulb)

$=1-{^{10}C}_0×(100\%-10\%)^{10}$

$=1-(\frac{9}{10})^{10}$