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Question 382011: i really need help please help me
1. Consider an experiment of picking a ball twice in a box with 4 different balls numbering from 1 to 4. The picked ball in the first try should be returned to the box for the second try.
1) Specify all the possible events from the experiment.
2) Find the probability of happening the event A, “the sum of the numbers from the two balls is 3”.
3) Find the probability of happening the event B, “the number of the 2nd ball is 2”.
4) Find the probability of happening the event of A and B.
5) Find the probability of happening the event of A after the event B happens.
6) Can we say that event A and B are mutually exclusive? If yes, why? or if not ,why not?
7) Can we say that event A and B are independent? If yes, why? or if not ,why not?

Click here to see answer by edjones(7569)

Question 382002: If the probability no one is late for class is 0.45, then the probability at least one person is late is
a. 0.45
b. 0.55
c. 0.65
d. 0.75
Click here to see answer by Fombitz(13828)

Question 382102: Find the fourth term without expanding the complete expression.
(9/x + x/9)^7
Click here to see answer by richard1234(5390)

Question 382090: how many ways can 1 card, not a face card, be drawn out of a deck 52 of cards? How do i set up the equation also?
Click here to see answer by richard1234(5390)

Question 382142: A bag contains 6 red marbles, 4 blue marbles, 7 white marbles and 9 yellow marbles. You are asked to draw 5 marbles from the bag without replacement. What is the probability of drawing less than two yellow marbles?
Click here to see answer by edjones(7569)

Question 382147: Help me to calculate the mean and range of the following clubs data:
Club A - 16.0,15.8,16.85,15.8,17.85,15.3,15.75,15.45
Club B - 15.95,16.9,16.85,17.85,15.25,17.5,17.0,17.25

Click here to see answer by rfadrogane(214)

Question 382163: 5 wooden blocks numbered 1,2,3,4,5 are placed by a young child in a row. What is the probability that the numbered formed is...
1. Less than 20,000?
2. More than 40,000?
Click here to see answer by Edwin McCravy(8908)

Question 382169: please help me with my homework i cannot do it :(
4. A random variable X follows the normal distribution, and another random variable Z follows the standard normal distribution
1) Explain the difference between the normal distribution and the standard distribution
2) Explain how the variables, X and Z are related.

Click here to see answer by stanbon(57307)

Question 382189: Determine the sample size if sample
standard deviation s : 6, population mean : 25,
sample mean = 23 and the degree of precision is
990/o
Click here to see answer by stanbon(57307)

Question 382118: a number from 20 to 29 is drawn at random. p(23) what is the probability

Click here to see answer by richard1234(5390)

Question 382194: Number 1 2 3 4 5 6
Occurences 34 32 36 35 34 31
A class rolled number cubes. Their results are shown in the table. What is the experimental probability of rolling a number less than 5?
a) 67.8%
b) 49.5%
c) 34.4%
d) 84.7%
Click here to see answer by stanbon(57307)

Question 382250: I am really confused!
1). Find the area under the standard normal curve for the following:
A). P(z < -1.14)
B). P(0 < z < 1.37)
C). P(-0.25 < z < 0.73)
2). Find the value of z such that approximately 35.08% of the distribution lies between it and the mean.
Click here to see answer by stanbon(57307)

Question 382255: A random sample of 121 observations from a population with a standard deviation of 50 yielded a sample mean of 150. Test the null hypothesis that the mean is 145 against the alternative at 10% level of significance.
Click here to see answer by stanbon(57307)

Question 382257: Can someone please explain this to me in words that I can understand? If someone could write out a sentence for me that explained what each part of this autocorrelation function properties means in Laymens terms I would really appreciate it.
|Rxx(τ) |≤Rxx(0)
Click here to see answer by stanbon(57307)

Question 382288: If the odds of winning a raffle are 17:200, what is the probability of winning?
Click here to see answer by stanbon(57307)

Question 382317: Please help me with these two homework problems. I have worked out both of them and keep getting them incorrect.
The average age of retirement residents is 69. The standard deviation is 5.8 years. A simple random sample of 100 residents is picked and the sample mean is computed.
1) What is the probability that the average age of the 100 residents is over 70?
2) Now suppose the sample had a 90% confidence interval for the population mean "u". This means?
For question #1, my answer was 0.4235. The second time I submitted the assignment, my answer was 0.0427. I used table a to come up with these answers.
For question #2 I said that it is an interval with a marginal error of greater than or less than 90%. I believe this is correct but is it also true that if this property was repeated, each time creating a new 90% interval, then in the long run 90% of those intervals would contain "u"?
Please help!
Click here to see answer by stanbon(57307)

Question 382362: Please help me to understand the margin of error and p-value better.
Does reducing standard deviation reduce margin of error?
Does lowering confidence level reduce the margin of error?
Is data only significant if the p-value is less than a?

Click here to see answer by stanbon(57307)

Question 382365: Please show me how to complete this problem:
Cheese weighs 8 oz, has a normal distribution mean of 8.1 oz, and a standard deviation of 0.1 oz.
There is a 5% chance the average weight of 5 samples will be below?
I said 8.03 oz. Is this correct?
Also, if 5 cheeses were selected, what would the probability that they are less than 8 oz?
I said 0.9873. Is this correct?
Click here to see answer by stanbon(57307)

Question 382376: is the following an example of deiscrete or continuous data:
a student recieved a grade of 18 correct out of 20 on a recent test.
Click here to see answer by stanbon(57307)

Question 382375: is the following an example of deiscrete or continuous data:
a student recieved a grade of 18 correct out of 20 on a recent test.
Click here to see answer by stanbon(57307)

Question 382335: Please help me with these two homework problems. I have worked out both of them and keep getting them incorrect.
The distribution of actual weight of 8 oz. cheese is normal mean with 8.1 oz. and standard deviation of 0.1 oz.
1. If a sample of five cheeses is selected, what is the probability their weight is less than 8 oz?
2. There is only a 5% chance that the five cheeses average age will be below?
For #1 I answered 0.9873. I did 8.1-8/(.1/sqrt5))
For #2 I answered 8.08 ounces.
Please help!
Click here to see answer by stanbon(57307)

Question 382258: Rxx(-τ)=Rxx (τ)

Can someone please explain this to me in words that I can understand? If someone could write out a sentence for me that explained what each part of this autocorrelation function properties means in Laymens terms I would really appreciate it.

Click here to see answer by stanbon(57307)

Question 382402: a bag contains 4 red tiles, 3 blue tiles, 2 green tiles, and 1 yellow tile. A tile is drawn from the bag and not returned. Then a second tile is drawn. What is the probability that the first tile is blue and the second tile is blue?
Click here to see answer by jim_thompson5910(28593)

Question 382254: I am not understanding this

1). x has a normal distribution with a mean of 80.0 and a standard deviation of 3.5 Find the following probabilities:
A). P(x < 75.0)
B). P(75.0 < x < 85.0)
C). P(x > 89.0)
2). A).Find the binomial probability P(x = 5), where n = 14 and p = 0.50
B).Set up, without solving, the binomial probability P(x is at most 5) using probability notation.
C). How would you find the normal approximation to the binomial probability P(x = 5) in Part A? Please show how you would calculate μ and σ in the formula for the normal approximation to the binomial, and show the final formula you would use without going through all the calculations.
Click here to see answer by stanbon(57307)

Question 382412: in a certain college 33% of the physics major are ethnic minorities. a random sample of 10 physics major is chosen find the probability that exactly 4 are not ethnic minorities. my answer is .0547 but Im not sure if this is right.
Click here to see answer by jim_thompson5910(28593)

Question 382415: a bag contains 6 cherry 3 orange and 2 lemon candies you reach in and take 3 pieces of candy at random find the probablity that you have all orange candies. I got 0.7272 not sure if that is right.
B. find the proability that you have 2 cherry and 1 lemon.
I also got .7272 for this.
Click here to see answer by jim_thompson5910(28593)

Question 382581: during world war II, american bomber crews suffered about 2% losses each mission. Crews were required to fly 50 missions. some crew members claimed that this made a 100% chance of getting shot down. what's wrong with this (what was their actual chance of getting shot down)?

Click here to see answer by stanbon(57307)

Question 382593: Suppose that the annual rate of return for a stock is normally distributed with a mean of 7% and a standard deviation of 4% . Find the probability that the one-year return of this stock will be positive? Round your answer to at least four decimal places.
Click here to see answer by stanbon(57307)

Question 382560: during world war II, american bomber crews suffered about 2% losses each mission. Crews were required to fly 50 missions. some crew members claimed that this made a 100% chance of getting shot down. what's wrong with this (what was their actual chance of getting shot down)?

Click here to see answer by stanbon(57307)

Question 303100: The average chocolate chip cookie contains 110 calories. A random sample of 15 different brands of 1-once chocolate chip cookies resulted in the following calorie amounts. At the α = 0.01 level, is there sufficient evidence that the average calorie content is greater than 110 calories?
100 125 150 160 185 125 145 155 160 100 150 140 135 120 110
Click here to see answer by tbaz(1)

Question 382634: There were 85 red balloons and 90 blue balloons at a party. What is the ratio of blue balloons to red balloons. Simplify your answer.
Click here to see answer by kingme18(98)

Question 382479: a bin contains 7 red chips , 9 green chips , 3 yellow chips, and 6 blue chips find each probability drawing a red chip replacing it then drawing a blue chip

Click here to see answer by stanbon(57307)

Question 382684: The spinner is divided in to 3 equal parts. The numbers of the parts are 1,2,3.
You spin the spinner two times. Question= you spin the spinner 1 both times.Find the probability.
Click here to see answer by kingme18(98)

Question 382708: John has made 80% of his free throws throughout his career.He has made 1500 successful free throws.How many attempts has he made?
Click here to see answer by richard1234(5390)

Question 382708: John has made 80% of his free throws throughout his career.He has made 1500 successful free throws.How many attempts has he made?
Click here to see answer by rfer(12657)

Question 382710: The scores on a standardized test had mean μ = 2.818 and standard deviation σ= 1.112. A teacher had 69 students take the test. Although the students were obviously not a random sample, she considered her students to be "typical" of all the national students. What is the probability that her students achieved an average score of at least 3?
Click here to see answer by stanbon(57307)

Question 382639: For a segment of a radio show, the DJ can play 6 songs. If he has 87 songs to choose from how many ways can the program for this segment be arranged
Click here to see answer by stanbon(57307)

Question 382737: I'm working on a homework assignment from my Topics in Mathematical Reasoning class and I've got an answer to this question, but there's no way for me to check the answer I have.
The question is:
A full house in poker consists of three of one kind and two of another kind in a five-card hand. For example, if a hand contains three Kings and two 5's, it is a full house. If 5 cards are dealt at random from a standard deck of 52 cards, without replacement, determine the probability of getting three Kings and two 5's.
My answer is 1/108,290
Click here to see answer by richard1234(5390)

Question 382740: 2 marbles are drawn without replacement from a box of 3 white 2 green 2 red and 1 blue marble. find the probablity
1. the second marble is blue given the first marble is red. so i got (rd) 1/4 and (blue) 1/7 so 1/4*1/7= 1/28 but my choices are 1/8 b. 1/4 c.1/7 or d. 2/7 so I am not sure what I am doing wrong.
2. the second marble is blue given the first marble is blue and I got 0 since there is only 1 marble is that correct?
Click here to see answer by stanbon(57307)

Question 382732: An official from the securities commission estimates that 75% of all investment bankers have profited from the use of insider information. Assume that 15 investment bankers are selected at random from the commission's registry. Using the Binomial Distribution, answer the following questions:
a. Find the probability that at most 10 have profited from insider information.
b. Find the probability that at least 6 have profited from insider information.
c. Find the probability that all 15 have profited from insider information.
d. What is the expected number of investment bankers who have profited from the use of insider information?
e. Find the variance and standard deviation of the number of investment bankers who have profited from the use of insider information.

Click here to see answer by stanbon(57307)

Question 382826: Suppose that the mean score of a class of 35 students was 76. The 15 male students in the class had a mean score of 66. What was the mean score for the 20 female students?
Click here to see answer by edjones(7569)

Question 382862: a die is tossed 4 times. what is the odds in favor of the die showing a 6 all four times.

Click here to see answer by stanbon(57307)

Question 382948: A spaceship has five life support systems. each has a 1% chance of failure during a flight. What is the probability that at least one of them will fail?
Click here to see answer by edjones(7569)

Older solutions: 1..45, 46..90, 91..135, 136..180, 181..225, 226..270, 271..315, 316..360, 361..405, 406..450, 451..495, 496..540, 541..585, 586..630, 631..675, 676..720, 721..765, 766..810, 811..855, 856..900, 901..945, 946..990, 991..1035, 1036..1080, 1081..1125, 1126..1170, 1171..1215, 1216..1260, 1261..1305, 1306..1350, 1351..1395, 1396..1440, 1441..1485, 1486..1530, 1531..1575, 1576..1620, 1621..1665, 1666..1710, 1711..1755, 1756..1800, 1801..1845, 1846..1890, 1891..1935, 1936..1980, 1981..2025, 2026..2070, 2071..2115, 2116..2160, 2161..2205, 2206..2250, 2251..2295, 2296..2340, 2341..2385, 2386..2430, 2431..2475, 2476..2520, 2521..2565, 2566..2610, 2611..2655, 2656..2700, 2701..2745, 2746..2790, 2791..2835, 2836..2880, 2881..2925, 2926..2970, 2971..3015, 3016..3060, 3061..3105, 3106..3150, 3151..3195, 3196..3240, 3241..3285, 3286..3330, 3331..3375, 3376..3420, 3421..3465, 3466..3510, 3511..3555, 3556..3600, 3601..3645, 3646..3690, 3691..3735, 3736..3780, 3781..3825, 3826..3870, 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7606..7650, 7651..7695, 7696..7740, 7741..7785, 7786..7830, 7831..7875, 7876..7920, 7921..7965, 7966..8010, 8011..8055, 8056..8100, 8101..8145, 8146..8190, 8191..8235, 8236..8280, 8281..8325, 8326..8370, 8371..8415, 8416..8460, 8461..8505, 8506..8550, 8551..8595, 8596..8640, 8641..8685, 8686..8730, 8731..8775, 8776..8820, 8821..8865, 8866..8910, 8911..8955, 8956..9000, 9001..9045, 9046..9090, 9091..9135, 9136..9180, 9181..9225, 9226..9270, 9271..9315, 9316..9360, 9361..9405, 9406..9450, 9451..9495, 9496..9540, 9541..9585, 9586..9630, 9631..9675, 9676..9720, 9721..9765, 9766..9810, 9811..9855, 9856..9900, 9901..9945, 9946..9990, 9991..10035, 10036..10080, 10081..10125, 10126..10170, 10171..10215, 10216..10260, 10261..10305, 10306..10350, 10351..10395, 10396..10440, 10441..10485, 10486..10530, 10531..10575, 10576..10620, 10621..10665, 10666..10710, 10711..10755, 10756..10800, 10801..10845, 10846..10890, 10891..10935, 10936..10980, 10981..11025, 11026..11070, 11071..11115, 11116..11160, 11161..11205, 11206..11250, 11251..11295, 11296..11340, 11341..11385, 11386..11430, 11431..11475, 11476..11520, 11521..11565, 11566..11610, 11611..11655, 11656..11700, 11701..11745, 11746..11790, 11791..11835, 11836..11880, 11881..11925, 11926..11970, 11971..12015, 12016..12060, 12061..12105, 12106..12150, 12151..12195, 12196..12240, 12241..12285, 12286..12330, 12331..12375, 12376..12420, 12421..12465, 12466..12510, 12511..12555, 12556..12600, 12601..12645, 12646..12690, 12691..12735, 12736..12780, 12781..12825, 12826..12870, 12871..12915, 12916..12960, 12961..13005, 13006..13050, 13051..13095, 13096..13140, 13141..13185, 13186..13230, 13231..13275, 13276..13320, 13321..13365, 13366..13410, 13411..13455, 13456..13500, 13501..13545, 13546..13590, 13591..13635, 13636..13680, 13681..13725, 13726..13770, 13771..13815, 13816..13860, 13861..13905, 13906..13950, 13951..13995, 13996..14040, 14041..14085, 14086..14130, 14131..14175, 14176..14220, 14221..14265, 14266..14310, 14311..14355, 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