In a bolt factory, machines A, B and C manufacture respectively 25%, 35%, 40% of the total. Of their output 5,4 and 2% are defective. A bolt is drawn at random from the product. What is the probability that the bolt drawn is defective?

A lot of 20 bulbs contains 4 defective ones. One bulb is drawn at random from the lot. What is the probability that the bulb is defective?

In a factory which manufactures bolts, machines A, B and C manufacture respectively 30%, 50% and 20% of the bolts. Of there outputs 3, 4, 1 percent respectively are defective bolts. A bolt is drawn at random from the product and is found to be defective. Find the probability that this is not manufactured by machine B.

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.

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

A lot of 20 bulbs contain 4 defective ones. Suppose the bulb drawn in (i) is not defective and is not replaced. Now one bulb is drawn at random from the rest. What is the probability that this bulb is not defective?

(i) A lot of 20 bulbs contain 4 defective ones. One bulb is drawn at random from the lot. What is the probability that this bulb is defective? (ii) Suppose the bulb drawn in (i) is not defective and is not replaced. Now one bulb is drawn at random from the rest. Whal is the probability that this bulb is not defective ?

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?

There are 5% defective items in a large bulk of items. What is the probability that a sample of 10 items will include not more than one defective item?