1. A stationary box contains 3 fountain pens, 5 pencils and 9 ball pens. If four items are drawn at random one by one without replacement, find the probability of getting all ball pens?

2. Ali shows symptoms of Malaria and advised by the doctor to get tested for confirmation. The prescribed test method comes positive 85% of the time the patient actually has Malaria. The test method gives false positive 10% of the time, i.e when the patient does not have Malaria. If 1.5% of the population is affected by Malaria, what is the probability that Ali has been infected by Malaria provided he tested positive?

3. A jar contains 7 marbles out of which 1 is red, 4 are yellow and 2 are blue. Two marbles are drawn at random with replacement, what is the probability of getting a blue or a red marble at the end of second trial?

4. In an intelligence test, a person is shown some colored cards one by one fastly, out of which 65% of were blue and 35% were green. The probability of surity given third card is green is 90%. Use this information to deduce how likely is it that the third card actually was green if the provided surity is used?

5. 19 apples in a carton have numbers written from 1 to 19. Three apples are taken out of the carton without replacement. What is the probability that all the apples have even numbers on them?