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प्रश्न
A flashlight has 8 batteries out of which 3 are dead. If two batteries are selected without replacement and tested, the probability that both are dead is ______.
पर्याय
`33/56`
`9/64`
`1/14`
`3/28`
उत्तर
A flashlight has 8 batteries out of which 3 are dead. If two batteries are selected without replacement and tested, the probability that both are dead is `3/28`.
Explanation:
Required probability = P(dead).P(dead)
= `3/8*2/7`
= `3/28`
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