All about Probabilities

1. A student is to answer 8 out of 10 questions in an exam. how many ways can the student take 3 different tests of 4 students are to take each test?

2. If repetition is not permitted, how many 3 digit numbers can be formed from the digits 2,3,5,6,7 and 9 if the number is odd?

3. There are 12 student in a class. In how many ways can the 12 students take 3 different test if 4 students are to take each test/

4. A class contain 10 students enrolled in JAVA and 20 students enrolled in C++. Half of the students enrolled in JAVA and half of the students in C++ are enrolled in statistics. Find the Probability that a student chosen at random is enrolled in JAVA or enrolled in STATISTICS.

5. Of 10 girls in a class, 3 have galaxy phones. If two girls are chosen at random what is the probability that neither has galaxy phones.

6. Box A contains 8 items of which 5 are colored red. Box B contain 5 items of which 3 are colored red. An item is drawn at random from each box. What is the probability that both items are colored red.

7. Three Bulbs are chosen at random from 15 bulbs of which 5 are defective. Find the Probability that at most 2 defective.

8. From #7, Find the probability that at least 1 is defective bulb.