Question

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? Multiple Choice 0.475 and 0.475 0.475 and 0.6892 0.50 and 0.6892 0.50 and 0.475

Answer 1

Answer: Fourth option is correct.

Explanation:

Since we have given that

Number of light bulbs = 10

Probability of defective bulbs = 5% = 0.05

Probability of non defective bulbs = 1-0.05 = 0.95

So, using "Binomial distribution", we get that :

`Mean=np=10* 0.05=0.5\\\\Variance=np(1-p)=npq=10* 0.05* 0.95=0.475`

Hence, Fourth option is correct.