Three electric lamps are to be fitted in a room.Three bulbs are chosen at random from 10 bulbs having 6 good bulbs and fitted. The chance that the room is lighted is

Three electric lamps are fitted in a room. 3 bulbs are chosen at random from 10 bulbs having 6 good bulbs. The probability that the room is lighted is

Three electric bulb holders are fixed in a room. 3 bulbs are chosen at random from a set of 20 bulbs of which 16 are good and fitted to the holders. What is the probability that the room is lighted.

3 bulbs are chosen at random from 20 bulbs , out of which 4 are defective . The probability that the room is illuminated will be

Three electric bulbs are chosen at random from 15 bulbs of which 5 are defective. The probability that atleast one is defective is

Three electric bulbs are chosen at random from 15 bulbs of which 5 are defective. The probability that atleast one is defective is

If 3 bulbs are selected from 12 bulbs of which 6 are good, then probability that at least one of them is good is

A room contains 3 sockets for bulbs. If from a collection of 10 bulbs, out of which 6 are defective, 3 bulbs are selected at random and put in the sockets, then the probability that the room is lighted is

A room contains 3 sockets for bulbs. If from a collection of 10 bulbs, out of which 6 are defective, 3 bulbs are selected at random and put in the sockets, then the probability that the room is lighted is

A room has 4 sockets for electric lamps. From a collection of 11 light bulbs of which 6 are good, 4 bulbs are selected at random and put in the sockets. Find the probability that the room does not suffer from a complete black-out.