KCET · Maths · Probability
A flashlight has \( 10 \) batteries out of which \( 4 \) are dead. If \( 3 \) batteries are selected without
replacement andtested, then the probability that all \( 3 \) are dead is
- A \( \frac{1}{30} \)
- B \( \frac{2}{8} \)
- C \( \frac{1}{15} \)
- D \( \frac{1}{10} \)
Answer & Solution
Correct Answer
(A) \( \frac{1}{30} \)
Step-by-step Solution
Detailed explanation
Total number of batteries are 10
Number of dead batteries is 4
So, P(all three dead)
\(=\frac{4}{10} \times \frac{3}{9} \times \frac{2}{8}=\frac{1}{30}\)
Number of dead batteries is 4
So, P(all three dead)
\(=\frac{4}{10} \times \frac{3}{9} \times \frac{2}{8}=\frac{1}{30}\)
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