Stats Study Guide

In a game, you have 1/36 probability of winning $95 and a 35/36 probability of losing$5. What is your expected value?

-$2.22

The chicken restaurant has a 46% recognition rate in a town. the owner wants to verify the recognition rate before opening a restaurant in that town. The owner randomly selects 12 residents, find the probability that exactly 6 residents recognize the brand.

0.217

A tennis player makes a successful first serve 52% of the time. If she sees 7 times, what is the probability that she gets exactly 3 first serves in bonds? assume that each serve is independent of the others.

0.261

find the probability of selecting exactly 4 toys.

0.273

An analysis of the registered voters in the last primary indicated that 55% of the voters were women. of the female voters, 35% were democrats, 35% were republicans, and the rest were Independents. of the male voters, the 30% were democrats, 45% were Republicans and 25% were independents. find the probability that a democrat chosen at random is male.

0.4122

Tommy flipped a fair coin 5 times which resulted in 5 tails in a row. what is the probability that the next fit will be heads?

0.5

find probability of selecting at least 4 toys

0.641

A circuit board has 10 identical components which function independently. the probability that a component will fail is 0.2. The circuit board will stop working if more than 3 of the components fail. find the probability that the circuit board will be working.

0.879

According to a survey of 19 year old college students, 18% of students work full time. Find the standard deviation for the number of 19 year old college students who work full time in samples of size 15.

1.488

suppose two cards are drawn from a single deck of 52 cards. find the probability of selecting a jack for the first card, replacing it in the deck, and then selecting a queen for the 2nd card.

1/169

in a bag there are 4 blue marbles, 3 red marbles, and 5 green. the first 3 drawn were green. what is the probability that the next 3 are blue?

1/21

In a statistics class there are 18 seniors and 10 juniors.6 of the juniors are females and 12 of the seniors are males. if a student is selected at random, find the probability of selecting a senior or a female.

24/28

A fair coin is tossed 5 times. what is the probability that at least 1 head occurs?

31/32

find the range. 55, 47, 25, 65, 52, 45

40

if a degree recipient is chosen at random, what is the conditional probability that the person chosen is male, given that the person chosen received a professional degree?

44/74

find the mode. 55, 56, 55, 59, 60, 58

55

Find the mean. 58, 52, 58, 68, 48, 55, 69,42, 69, 51

57

Which question is biased?

Do you prefer watching the news or mindless sitcoms?

what is meant by "standardizing" the values in the data set?

For each data value, subtract the mean and divide by the standard deviation (i.e., calculate the "z-score" for each data value)

Which of the following is true?

If events A and B are ot independent, then they may be either mutually exclusive or not mutually exclusive

The "Normal Distribution" is considered an important probability distribution in the field of statistics. Why is this?

Many real world data are approx. normally distributed. and in certain cases, many sampling distributions of sample statistics are approx. normally distributed.

What is the best measure of center? 55, 58, 25, 52, 53, 56

Median because the data contains an outlier

Determine whether the given procedure results in a binomial distribution. if not, state the reason why. Rolling a single die 25 times, keeping track of the numbers that are rolled.

Not binomial, tere armere than 2 outcomes for each trial.

What is the sample space for the experiment of Jim and Karley having 2 childrenn? Use B for Boy and G for Girl

S= {BB, BG, GB, GG}

two 6 sided dice are rolled and the sum S is recorded. Which of the following events has a probability =1?

S_<13

Select a random sample of5 state capitals from the list below

Springfield; Atlanta; Providence; Santa Fe; Columbus

which of the following is not a measure of center?

Standard Deviation

A hospital administrator is concerned about the quality of food in the cafe. He wants to sample some of the patients. to do this he surveys 10 patients on each of the 7 floors. What kind sample did he take?

Stratified

He wants to sample the patients. to do this, he surveys every 10th patient based on when they arrived. What kind of sample is this?

Systematic

If one is to use the "z-scores" and the "z-table" to get reasonable answers to questions about the probability of an observation being above or below some value for a particular phenomenon, what must be true about this phenomenon?

The phenomenon must be approx. normally distributed

find the mode. 4, 8, 6, 2, 1, 9

There is no mode

A hospital administrator is concerned about the quality of food in the cafe. he wants to sample some of the patients at the hospital. To do this, he surveys every patient on the1st,2nd, and 5th floors. what kind of sample did the administrator take?

cluster

a hospital administrator is concerned about the quality of the food in the cafeteria. he wants to sample some of the patients at the hospital. to do this, he has a nurse survey all of her patients as she makes her round. what kind of sample did the administrator take?

convenience sample

A scientist is studying the Wooly Adelgid parasite in Hemlock trees. To test the effectiveness of a new spray to cue this, the scientist uses the spray on a section of Hemlock trees. After 2 months they compare the number of parasites in the trees that were treated with the spray versus the trees that were not treated with the spray versus the trees that were not treated with the spray. This is an example of:

experiment

A researcher obtained random sample of 100 smokers and a random sample 100 nonsmokers. After interviewing all 200 participants in the study, the researcher compared the rate of depression among the smokers with the rate of depression among the nonsmokers. this is an example of:

observational study

Although 14% of students are left handed, in a random sample of 20 students, 5 were left handed. This is an example of

sampling error

a bottling company claims that 60% of the bottles are overfilled. suppose that 800 bottles are selected at random from the production lines. would it be unusual for this sample of 800 bottles to contain 575 bottles or more that are overfilled?

yes