Questions on Algebra: Probability and statistics answered by real tutors!

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Question 426918: How do I find the area under the standard normal curve between z = .84 and z = 1.95.
Click here to see answer by Edwin McCravy(8908)

Question 426971: Help me please, I am going to flunk this class if I don't get at least one answer correct!
What critical region(s) for z would be used to test the hypotheses: H_0:μ=10 and H_a:μ≠10, for a = 0.05 ?
Click here to see answer by ewatrrr(10682)

Question 426942: What is the smallest sample size if we want to estimate the population mean with a 95% confidence, a standard deviation of 60 and have the precision within (plus-minus) 5?
Click here to see answer by robertb(4012)

Question 426968: If I have a bag that has 13 red candies, 13 yellow candies, 13 green candies and 13 blue candies, what is the probability that if I pick one it will not be blue?
Click here to see answer by ewatrrr(10682)

Question 426914: Caroline has a 67% chance of receiving an A grade in statistics, a 51% chance of receiving an A grade in mathematics, and a 41% chance of receiving A grades in both statistics and mathematics. Find the probability that she receives an A in statistics or mathematics (or both).

Click here to see answer by robertb(4012)

Question 427247: 1. A multiple choice test has 30 questions, and each has five possible answers, of which one is correct. If a student guesses on every question, find the probability of getting exactly 40% correct.
I understand n=30 and p=0.20 but the 40% correct is confusing me. Please help.
2. What is the probability that 4 rolls of a fair die will show exactly three fours?
Click here to see answer by edjones(7569)

Question 427216: The weight of food packed in certain containers has a mean of 16 ounces and a standard deviation of 0.6 ounces. There are 36 containers placed in a box for shipping. Find the probability that a randomly picked box will weight over 580 ounces.
Click here to see answer by robertb(4012)

Question 427342: 1. A card is drawn from an ordinary deck and we are told that it is red, what is the probability that the card is greater than 2 but less than 9?
Click here to see answer by sudhanshu_kmr(1152)

Question 427371: A salesperson determines that the probability of making a sale to a customer is 1/9. What is the probability of making a sale to eight of the next seventeen customers?
Click here to see answer by sudhanshu_kmr(1152)

Question 427377: Matt flipped two fair coins together. He continued doing so until at least one of the coins turns up heads. What is the probability that both are heads on the last flip?
Click here to see answer by sudhanshu_kmr(1152)

Question 423795: 6.2% of DVD players of a certain type are defective. Let the random variable X represent the number of defective dvd players among 200 randomly selected DVDs of this type. Does the random variable have a binomial distirbution or a poisson distribution
Find P(x<8)
Click here to see answer by hagc(1)

Question 427431:
What is the probability of guessing the correct answer on a multiple choice question with five possible answers?
Click here to see answer by shree840(260)

Question 427430: What is the probability of a sunny day after a forecast of a 45% chance of precipitation?
Click here to see answer by shree840(260)

Question 427428: What is the probability of drawing 3 aces out of a standard deck of 52 cards when the drawn card is not returned to the deck each time?
Click here to see answer by shree840(260)

Question 427420: In a statistics class with 15 males and 13 females, five students are selected to put problems on the board. What is the probability that:
a. 3 females and 2 males are selected?

b. all five students selected are males?

c. all five students selected are females?

d. at least one male is selected?

Click here to see answer by ewatrrr(10682)

Question 427564: Of the following measures: median, mean, interquantile range, and standard deviation' which are not affected by the presence of outliers?
Click here to see answer by stanbon(57314)

Question 427457: Suppose that 32% students are addicted to chocolate. If 10 students are randomly selected, what is the probability that at least one of them is addicted to chocolate? Round your answer to five decimal places.
Click here to see answer by stanbon(57314)

Question 427437: Using normal approximation, what is an estimation of the probability of getting more than 51 girls in 100 births, assuming that boys and girls are equally likely.
Click here to see answer by stanbon(57314)

Question 427427: Your child is in a 3rd grade class of 15 boys and 16 girls. 10 of the boys love the movie "Star Wars" and 9 of the girls love "Star Wars." What is the probability that a student chosen at random is a girl or loves "Star Wars?"
Click here to see answer by stanbon(57314)

Question 427346: i need to find the z values for a normal distribution
were the mean is 75 and standard deivation is 21
- the probability that exceeds 19%
and were the mean is 21 and the stanard deivation is 6
-the probability the exceed 21%
thanks
Click here to see answer by stanbon(57314)

Question 427626: there are three men and 4woman standing in a line the man must stand together how many lines are possible?
Click here to see answer by sudhanshu_kmr(1152)

Question 427604: A company has 20 employees, 12 male and 8 female. How many ways are there to form a 5 person committee that contains at least one male and at least one female?
Click here to see answer by sudhanshu_kmr(1152)

Question 427635: What is the mean of all 5-digit numbers made up of one of each of the digits 1 through 5?
Click here to see answer by ewatrrr(10682)

Question 427624: The average diameter of certain Euro coins 3.00 millimeters with a standard deviation of
0.70 millimeters. If 9 coins are chosen at random, find the probability that the average
diameter of those coins is more than 2.790 millimeters. Assume that the variable is
normally distributed.
Click here to see answer by ewatrrr(10682)

Question 427601: pls. help me solve this problem... thank you
a normal distribution has the mean of 160.5. if 75% of the area under the curve lies to the left of 185.2 find:
a. the area to the left of 160.5
b. the area to the right of 185.2
c. the area between 160.5 and 185.2
d. the standard deviation
e. the area betweem 160.5 and 180.5
f. the area to the right of 180.5
Click here to see answer by ewatrrr(10682)

Question 427605: Simplified radical form and rationalize all denominator
(3√(7))/(-1-√(27))
Click here to see answer by stanbon(57314)

Question 427593: I have two questions:
Which of these is not true of the mean(x-bar) of the lengths and inches of a sample of brook trout?
(a) x-bar must take a value greater than zero
(b) x-bar is measured in inches
(c) x-bar would not change if we measured these trout in centimeters instead of
inches.
(d) Both b & c
(e) Both a & c
My next question is:
Which of these is not true of this standard deviation (s) of the lengths and inches of a sample brook trout?
(a) s must take a value between -1 and 1
(b) s is measured in inches
(c) s will not change if we measured these trout in centimeters instead of
inches.
(d) Both b & c
(e) Both a & c
Click here to see answer by stanbon(57314)

Question 427580: A sample of n=25 scores produces a tcal of -2.05. If the researcher is using a two tailed test with α =0.05 the correct statistical decision is?
A. REject the null hypotheses - significant
B.- fail to reject the null hypotheses
Click here to see answer by stanbon(57314)

Question 427435: Suppose a company wants to do random drug testing of its employees and that 2% of the employees use illegal drugs. If the test for detecting drug use is given to people who use illegal drugs, it returns a positive result 99% of the time. When the test is given to people who do not use drugs, it returns a positive result 6% of the time. What is the probability that an employee who receives a positive test result actually does NOT use drugs? (hint..use a tree using "user" and "non-user" instead of "ill" and "healthy") Round to four decimal places.
There are 20 grapefruit in a basket. 9 are sweet, and 11 are sour. If you select 2 at random,what is the probability that they will all be sweet? (Round the answer to four decimal places.)
Click here to see answer by stanbon(57314)

Question 427651: You have four different history books, three different biology books, and two different math books. In how many different ways can you line these books up on a shelf if books of the same type have to be next to each other?
Click here to see answer by stanbon(57314)

Question 427710: A researcher collected sample data for 12 women ages 18 to 24. The sample had a mean serum cholesterol level (measured in mg/100 mL) of 189.9 , with a standard deviation of 5.5. Assuming that serum cholesterol levels for women ages 18 to 24 are normally distributed, find a 99% confidence interval for the mean serum cholesterol level of all women in this age group.
Click here to see answer by stanbon(57314)

Question 427696: Four Balls are selected without replacement from an urn containing three white balls and five blue balls. What is the probability that all balls selected are blue?
Click here to see answer by stanbon(57314)

Question 427689: We need to create serial numbers that start with one of the letters a, b, c, d, or f followed by three non-repeating digits. How many serial numbers can be created?
Click here to see answer by stanbon(57314)

Question 427686: How many different 5-letter "words" are there which read the same forward as backward? (We use only capital letters and, of course, repeats are allowed.)
Click here to see answer by stanbon(57314)

Question 427682: You have four different history books, three different biology books, and two different math books. In how many different ways can you pick one book of each type to take with you on a trip?
Click here to see answer by jorel1380(2518)

Question 427858: 8- When an experiment is performed, one and only one of the events A₁, A₂ and A₃ will occur. Find P (A₁), P (A₂) and P (A₃) under each of the following assumptions:
a) P(A₁) = P(A₂) = P(A₃)
b) P(A₁) = P(A₂) and P(A₃) = 1/2
c) P(A₁) = 2P(A₂) = 3P(A₃)
pleeeeease .. need ur help ..!

Click here to see answer by sudhanshu_kmr(1152)

Question 427890: how many ways can you stack 12 books in a single stack?

Click here to see answer by stanbon(57314)

Question 427771: A pair of fair dice is rolled. What is the probability that the sum of the numbers falling uppermost is less that 9 given that at least one of the number is a 6?
Click here to see answer by stanbon(57314)

Question 427898: how many ways can you stack 12 books in a single stack?
Click here to see answer by stanbon(57314)

Question 427924: An electronics manufacturer has found that only 1 out of 500 of its television sets is defective. You are ordering a shipment of television sets for the electronics store where you work. How many television sets can you order before the probability that at least on defective set reaches 60%?
Click here to see answer by stanbon(57314)

Question 427915: if the word tennessee is placed on a piece of paper all nine letters are placed in the hat what is the probability that the letter T or N is selected
Click here to see answer by stanbon(57314)

Question 427894: heights of men on a baseball team have a bell-shaped distribution with a mean of 180 cm and a standard deviation of 8 cm. Using the empirical rule, what is the approximate percentage of the men between the following values? 156 cm and 204 cm
Click here to see answer by stanbon(57314)

Question 427959: a total of 800 people were interviewed and asked to name the Vice President of the U.S. Of these 575 people answered correctly. find the probability that the next person asked can NOT correctly identify the Vice President.
Click here to see answer by stanbon(57314)

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