If a machine is correctly set up, it produces 90% acceptable items. If it is incorrectly set up, it produces only 40% acceptable items. Past experience shows that 80% of the set ups are correctly done. If after a certain set up, the machine produces 2 acceptable items, find the probability that the machine is correctly setup.

In a tape recorder factory three machines A, B and C produced 50%, 30% and 20% of total production. The percentage of the defective output of these machines are 2%, 5% and 10% respectively. A tape recorder is selected randomly and found to be defective, find the probability that it is produced by machine A.

A manufacturer has three machine operators A, B and C. The first operator A produces 1% defective items, where as the other two operators B and C produce 5% and 7% defective items respectively. A is on the job for 50% of the time, B is on the job for 30% of the time and C is on the job for 20% of the time. A defective item is produced, what is the probability that it was produced by A?

In a tape recorder factory, three machines A, B and C produced 25%, 35% and 40% respectively. The percentage of defective output of these machines are 5%, 4% and 2% respectively. A tape recorder is selected at random and is found to defective. Find the probability that tape recorder is produced by machine B .

Three machines E_1, E_2, E_3 in a certain factory produce 50%, 25% and 25% respectively of the total daily output of electric tubes. It is known that 4% of the tubes produced by each of machines E_1 and E_2 are defective, and that 5% of those produced on E_3 are defective. If one tube is picked up at random from a day's production, calculate the probability that it is defective.

ln a tape recorder factory, three machines A, B and C produced 40%, 30% and 20% of total production. The percentage of the defective output of these machines are 2%, 3% and 4% respectively. A tape recorder is selected at random and found to be defective. Find the probability that tape recorder is produced by machine C.

A factory has two machines A and B. Past record shows that machine A produced 60% of the items of output and machine B produced 40% of the items. Further, 2% of the items produced by machine A and 1% produced by machine B were defective. All the items are put into one stockpile and then one item is chosen at random from this and is found to be defective. What is the probability that it was produced by machine B?

10% of the bulbs produced in a factory are red colour and 2% are red and defective. If one bulb is picked up at random, determine the probability of its being defective if it is red.

Draw a labelled diagram of Hertz's experiment set up to produce electromagnetic waves. Explain the generation of electromagnetic waves using this set up.

An item is manufacture by three machines A, B and C. out of the total number of items manufactured during a specified period, 50% are manufactures on A. 30% on B and 20% on C. 2% on the items produced on A and 2% of items produced on B are defective, and 3% of these produced on C are defective. All the items are stored at one godown. One item is drawn at random and is found to be defective. what is the probability that it is manufactured on machine A?