Exam 4: Basic Probability

TABLE 4-12 Jake woke up late in the morning on the day that he has to go to school to take an important test.He can either take the shuttle bus which is usually running late 20% of the time or ride his unreliable motorcycle which breaks down 40% of the time.He decides to toss a fair coin to make his choice. -Referring to Table 4-12,if Jake is late to the test,what is the probability that he took the bus?

If P(A and B)= 0,then A and B must be mutually exclusive.

If P(A)= 0.4 and P(B)= 0.6,then A and B must be mutually exclusive.

TABLE 4-3 A survey is taken among customers of a fast-food restaurant to determine preference for hamburger or chicken.Of 200 respondents selected,75 were children and 125 were adults.120 preferred hamburger and 80 preferred chicken.55 of the children preferred hamburger. -Referring to Table 4-3,assume we know the person is a child.The probability that this individual prefers hamburger is ________.

The probability that house sales will increase in the next 6 months is estimated to be 0.25.The probability that the interest rates on housing loans will go up in the same period is estimated to be 0.74.The probability that house sales or interest rates will go up during the next 6 months is estimated to be 0.89.The probability that both house sales and interest rates will increase during the next 6 months is

To ethically advertise a school lottery scheme to try to raise money for the athletic department,the organizer of the lottery does not need to explicitly specify the probability of each of the prize in the lottery.

TABLE 4-6 At a Texas college,60% of the students are from the southern part of the state,30% are from the northern part of the state,and the remaining 10% are from out-of-state.All students must take and pass an Entry Level Math (ELM)test.60% of the southerners have passed the ELM,70% of the northerners have passed the ELM,and 90% of the out-of-staters have passed the ELM. -Referring to Table 4-6,the probability that a randomly selected student has passed the ELM is ________.

When using the general multiplication rule,P(A and B) is equal to

TABLE 4-3 A survey is taken among customers of a fast-food restaurant to determine preference for hamburger or chicken.Of 200 respondents selected,75 were children and 125 were adults.120 preferred hamburger and 80 preferred chicken.55 of the children preferred hamburger. -Referring to Table 4-3,assume we know that a person prefers hamburger.The probability that this individual is a child is ________.

Twelve students in a Business Statistics class are to be formed into three teams of four.How many different ways can this be done?

Suppose A and B are events where P(A)= 0.4,P(B)= 0.5,and P(A and B)= 0.1.Then P(A or B)= ________.

TABLE 4-9 A survey conducted by the Segal Company of New York found that in a sample of 189 large companies,40 offered stock options to their board members as part of their non-cash compensation packages.For small- to mid-sized companies,43 of the 180 surveyed indicated that they offer stock options as part of their noncash compensation packages to their board members. -Referring to Table 4-9,is the size of the company independent of whether stock options are offered to their board members and why?

The probability that house sales will increase in the next 6 months is estimated to be 0.25.The probability that the interest rates on housing loans will go up in the same period is estimated to be 0.74.The probability that house sales or interest rates will go up during the next 6 months is estimated to be 0.89.The events increase in house sales and no increase in house sales in the next 6 months are

If two events are mutually exclusive and collectively exhaustive,what is the probability that both occur?

TABLE 4-1 Mothers Against Drunk Driving is a very visible group whose main focus is to educate the public about the harm caused by drunk drivers.A study was recently done that emphasized the problem we all face with drinking and driving.Four hundred accidents that occurred on a Saturday night were analyzed.Two items noted were the number of vehicles involved and whether alcohol played a role in the accident.The numbers are shown below: -Referring to Table 4-1,given that alcohol was not involved,what proportion of the accidents were single vehicle?

If two equally likely events A and B are mutually exclusive and collectively exhaustive,what is the probability that event A occurs?

TABLE 4-4 Suppose that patrons of a restaurant were asked whether they preferred water or whether they preferred soda.70% said that they preferred water.60% of the patrons were male.80% of the males preferred water. -Referring to Table 4-4,the two events "preferring water" and "being a male" are independent.

Four freshmen are to be assigned to eleven empty rooms in a student dormitory.All the rooms are considered as homogenous so that it does not matter who is being assigned to which room.How many different ways can those 4 freshmen be assigned?

The collection of all possible events is called

Eleven freshmen are to be assigned to eleven empty rooms in a student dormitory.Each room is considered unique so that it matters who is being assigned to which room.How many different ways can those eleven freshmen be allocated?