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scoundrel [369]
3 years ago
9

On a particular production line,the likelihood that a light bulb is defective is 5%. Ten light bulbs are randomly selected. What

are the mean and variance of the number of defective bulbs?
Mathematics
1 answer:
KengaRu [80]3 years ago
5 0

Answer:

Mean and Variance of the number of defective bulbs are 0.5 and 0.475 respectively.

Step-by-step explanation:

Consider the provided information,

Let X is the number of defective bulbs.

Ten light bulbs are randomly selected.

The likelihood that a light bulb is defective is 5%.

Therefore sample size is = n = 10

Probability of a defective bulb = p = 0.05.

Therefore, q = 1 - p = 1 - 0.05 = 0.95

Mean of binomial random variable: \mu=np

Therefore, \mu=10(0.05)=0.5

Variance of binomial random variable: \sigma^2=npq

Therefore, \sigma^2=10(0.05)(0.95)=0.475

Mean and Variance of the number of defective bulbs are 0.5 and 0.475 respectively.

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Answer:

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Step-by-step explanation:

Given that:

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