More Exercises in Probability: ADDITION & MULTIPLICATION RULES

Please enter your name

1. A package of Easter M&M's yielded 22 blue, 35 pink, 12 yellow, and 28 green M&M's. If an M&M is randomly selected, what is the probability that the M&M was purple?

P(purple) = 0.000.
P(purple) =1.000.
P(purple) = 0.361.
P(purple) = 639.


2. A package of Easter M&M's yielded 22 blue, 35 pink, 12 yellow, and 28 green M&M's. If two M&M's are randomly selected, without replacement, what is the probability that the first is pink and the second is yellow?
P(pink and yellow) = 0.4850.
P(pink and yellow) = 0.0446.
P(pink and yellow) = 0.0288.
P(pink and yellow) = 0.0451.


3. Given a well shuffled deck of standard playing cards, what is the probability of randomly selecting either a black card or an even numbered card (2, 4, 6, 8, 10)?

P(black or even) = 0.692.
P(black or even) = 0.885.
P(black or even) = 0.308.
P(black or even) = 0.115.


4. According to the Baltimore Sun (Wednesday, March 11, 1998) Anne Arundel county health officials inspected 128 restaurants and found 28 had critical food-safety violations that were corrected. If 2 restaurants (out of the 128) are randomly selected, what is the probability that both had critical food-safety violations that were corrected?

P(both had food-safety violations that were corrected) = 0.259.
P(both had food-safety violations that were corrected) = 0.
P(both had food-safety violations that were corrected) = 0.047
P(both had food-safety violations that were corrected) = 0.0096.


5. According to the Consumer Reports website, Consumer Union did a nationwide survey of owners of manufactured (mobile) homes. The report determined that 6 out of 10 (or 60%) of the people had major problems with their homes. If 5 manufactured home owners are randomly selected, what is the probability that at least one of them had major problems with their homes?

P(at least one had major problems) = 99.0%.
P(at least one had major problems) = 92.2%.
P(at least one had major problems) = 40.0%.
P(at least one had major problems) = 60.0%.


6. According to the NCHS, in 1993 25% of all adults smoked cigarettes. If 3 people are randomly selected, what is the probability that all of them smoke?

P(all smoked) = 6.25%.
P(all smoked) = 1.6%.
P(all smoked) = 25%.
P(all smoked) = 75%.


7. According to USA Today (March 12, 1998), 83% of adults 18 - 24 years of age go to the movies at least once a month. If 2 adults between 18 - 24 are randomly selected, what is the probability that at least one of them go to the movies at least once a month?

P(at least one goes to the movies at least once a month) = 0.311.
P(at least one goes to the movies at least once a month) = 0.0289.
P(at least one goes to the movies at least once a month) = 0.689.
P(at least one goes to the movies at least once a month) = 0.971.


8. When answering questions involving the addition rule of probability, what is the "key" question that you should ask yourself?

Are the two events independent?
Are the two events mutually exclusive?
Do I care about these two events?
None of the above.