A box contains 16 bulbs, out of which 4 bulbs are defective. Three bulbs are drawn at random from the box. Let X be the number of defective bulbs drawn. Find the mean and variance of X.

Three defective bulbs are mixd with 7 good ones. Let X be the number of defective bulbs when 3 bulbs are drawn at random. Find the mean and variance of X.

A box contains 12 bulbs of which 3 are defective. A sample of 3 bulbs is selected from the box. Let X denotes the number of defective bulbs in the sample, find the probability distribution of X.

A box contains 16 bulbs out of which 4 bulbs are defective. 3 bulbs are drawn one by one from the box without replacement. Find the probability that all three are defective bulbs

A box contains 16 bulbs out of which 4 bulbs are defective. 3 bulbs are drawn one by one from the box without replacement. Find the probability distribution of the number of defective bulbs.

A box contains 13 bulbs out of which 5 bulbs are defective. 3 bulbs are drawn one by one from the box without replacement. Find the probability that exactly 2 bulbs are defective.

A box contains 100 bulbs, out of which 10 are defective. A sample of 5 bulbs is drawn. The probability that none is defective is

A box contains 100 bulbs out of which 10 are defective. A sample of 5 bulbs is drawn. The probability that none is defective , is

A box contains 100 bulbs out of which 10 are defective. A sample of 5 bulbs is drawn. The probability that none is defective , is