1. A certain store sells small, medium, and large toy trucks in each of the colors red, blue, green, and yellow. The store has an equal number of trucks of each possible color size combination. If Stella wants a medium, red truck and her mother will randomly select one of the trucks in the store, what is the probability that the truck she selects will have at least one of the two features Stella wants?
a) 1/4 b) 1/3 c) 1/2 d) 7/12 e) 2/3
2. A box contains 100 balls, number from 1 to 100. If three balls are selected at random and with replacement from the box, what is the probability that the product (multiplication) of the three numbers will be even?
a) 1/8 b) 1/2 c) 3/4 d) 7/8 e) 15/16
3. Let A be the event that a randomly selected two digit number is divisible by 3 and let B be the event that a randomly selected two digit number is divisible by 4. What is P(A and B)?
a) 1/45 b) 2/45 c) 1/15 d)1/9 e) 1/3
4. A string of 10 lightbulbs is wired in such a way that if any individual light bulb fails, the entire string fails. If for each individual lightbulb the probability of failing during a certain time period is 0.06, what is the probability that the string of lightbulbs will fail during said time period?
a) 0.06 b) (0.06)^10 c) 1- (0.06)^10 d) (0.94)^10 e) 1 - (0.94)^10
5. There are 10 solid-colored balls in a box including 1 green ball and 1 yellow ball. If 3 of the balls in the box are to be chosen at random, without replacement, what is the probability that the 3 balls chosen will include the green ball but NOT the yellow ball?
a) 1/6 b) 7/30 c) 1/4 d) 4/15 e) 3/10
6. If a committee of 3 people is to be selected from among 5 married couples, what is the probability that the committee does NOT include a married couple?
a) 1/6 b) 1/3 c) 5/12 d) 2/3 e) 1
7. A couple decides to have 4 children. If they succeed in having 4 children and each child is equally likely to be a boy or a girl, what is the probability that they will have exactly 2 girls and 2 boys?
a) 3/8 b) 1/4 c) 3/16 d) 1/8 e) 1/16
8. sixty percent of the members of a study group are women, and 45 percent of those women are lawyers. If one member of the study group is to be selected at random, what is the probability that the member selected is a woman lawyer?
a) 0.1 b) 0.15 c) 0.27 d) 0.33 e) 0.45
9. Alfred, Betsy, and Charlotte each try independently to solve a problem. If their individual probabilities for success are 1/4, 1/2 and 5/8, respectively, what is the probability that Alfred and Betsy, but NOT Charlotte, will successfully solve the problem?
a) 11/8 b) 7/8 c) 9/64 d) 5/64 e) 3/64