1 What is the probability of getting either a sum of 6 or at

1. What is the probability of getting either a sum of 6 or at least one 6 in the roll of a pair of dice?

2. The mathematics faculty at a college consists of 4 professors, 4 associate professors, 11 assistant professors, and 4 instructors. If one faculty member is randomly selected, find the probability of choosing a professor or an instructor.

3. The numbers 1,2,3,4, and 5 are written on slips of paper, and 2 slips are drawn at random one at a time without replacement. Find the given probabilities.

the probability that the sum of the numbers is 9 is:

the probability that the sum of the numbers is 6 or less is:

the probability that the first number is 2 or the sum is 5 is:

4. A marble is selected at random from a jar containing 2 red marbles, 5 yellow marbles, and 4 green marbles. What are the odds in favor of selected a red marble?

5. Suppose that 12% of a certain batch of calculators have a defective case, and that 13% have defective batteries. Also, 5% have both a defective case and defective batteries. A calculator is selected from the batch at random. Find the porbability that the calculator has a good case and good batteries.

Solution

Q(1)

(sum = 6) outcomes
(1,5) (2,4) (3,3) (4,2) (5,1)
total 5

atlest one six out comes
(1,6). (2,6), (3,6), (4,6), (5,6), (6,6), (6,1), (6,2), (6,3), (6,4), (6,5)
total=11

including both
total outcomes =16

so probability = 16/36 = 4/9