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?

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?

A factory has three machines X,Y and Z producing 1000, 2000 and 3000 bolts per day respectively. The machine X produces 1% defective bolts, Y produces 1.5% and Z produces 2% defective bolts. At the end of a day, a bolt is drawn at random and is found defective. what is the probability that the defective bolt is produced by the machine X?

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?

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 3%, 4% and 5% respectively. A tape recorder is selected randomly and found to be defective, find the probability that it is produced by machine A.

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.

The items produced by a company contain 10% defective items. Show that the probability of getting 2 defective items in a sample of 8 itmes is frac{28xx9^6}{10^8} .

There are 6% defective items in a large bulk of items. Find the probability that a sample of 8 items will include not more than one (or less than two) defective item.

In a bolt factory, three machines A, B and C manufacturers 25 , 35 and 40 percent of the total bolts . Of their output 5 , 4 and 2 percent are defective respectively. A bolt is drawn at random and found to be defective. Find the probability that it was manufactured by machine B.