Neelam is taking up subjects - Mathematics, Physics and Chemistry. She estimates that her probabilities of receiving a grade A in these courses. are 0.2, 0.3 and 0.9 respectively. If the grades can be regarded as independent events, find the probabilities that Neelam receives :
Exactly two A’s .

Neelam is taking up subjects - Mathematics, Physics and Chemistry. She estimates that her probabilities of receiving a grade A in these courses. are 0.2, 0.3 and 0.9 respectively. If the grades can be regarded as independent events, find the probabilities that Neelam receives : All A’s .

Three persons A,B and C apply for a job of manager in a private company. Chances of their selection are in the ratio 1:2:4. The probabilities that A,B and C can introduce changes to improve profits of the company are 0.8, 0.5 and 0.3 respectively. If the change does not take place, find the probability that it is due to appointment of C.

Three persons A, B and C apply for a job of Manager in a Private Company. Chances of their selection (A, B and C) are in the ratio 1 : 2 : 4. The probabilities that A, B and C can introduce changes to improve profits of the company are 0.8, 0.5 and 0.3 respectively. If the change does not take place, find the probability that it is due to the appointment of C.

The probability that a student will receive an A, B, C or D grade is 0.40, 0.35, 0.15 and 0.10 respectively. Find the probability that a student will receive : not an A grade.

The probability that a student will receive an A, B, C or D grade is 0.40, 0.35, 0.15 and 0.10 respectively. Find the probability that a student will receive : at most a C grade.

The probability that a student will receive an A, B, C or D grade is 0.40, 0.35, 0.15 and 0.10 respectively. Find the probability that a student will receive : B or C grade.

There are two independent events E_1 and E_2 and P(E_1)=0.30 , P(E_2)=0.60 find the probability that neither E_1 nor E_2 occurs.

For three persons A, B and C the chances of being selected as Manager of a firm are in the ratio 4:1:2 respectively. The respective probabilities for them to introduce a radical change in marketing strategy are 0.3, 0.8 and 0.5. If the change does take place, find the probability that it is due to the appointment of B or C.

There are two independent events E_1 and E_2 and P(E_1)=0.30 , P(E_2)=0.60 find the probability that one and only one event happens.

There are two independent events E_1 and E_2 and P(E_1)=0.30 , P(E_2)=0.60 find the probability that both E_1 and E_2 occur.