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Question 435513: A pair of dice are tossed. What is the probability that doubles are rolled, given that the sum on the two dice is less than 7? (Round your answer to three decimal places.)

Click here to see answer by Edwin McCravy(8891)

Question 435538: A pair of dice are tossed. What is the probability that doubles are rolled, given that the sum on the two dice is less than 12? (Round your answer to three decimal places.
Click here to see answer by stanbon(57282)

Question 435548: Hi!
I have a question on probability. Can you please tell me how I would go about solving this question: A family has two children. What is the probability that the second child is a boy given the first is a girl?
Click here to see answer by shree840(260)

Question 435545: Hi!
So, I have a question on probability. The question is students in the class take two tests. 20% of the class passed both tests and 57% of the class passed the first test. What percentage of those who passed the first test also passed the second test?
Thank you for your help!
Click here to see answer by stanbon(57282)

Question 435550: Hi!

I have a question on a probability problem. You draw a five card hand from a deck of 52 cards and nd that you are 2 cards away from a Flush. What is the probability that, if you remove the two bad cards, you will pull the correct cards from the deck to make a Flush?
Click here to see answer by shree840(260)

Question 435553: Hi!
I have a probability question: A family has three children. What is the probability that one is boy given that one is a girl?
Thank you for your help!
Click here to see answer by scott8148(6628)

Question 435554: Hi!

I have a quick probability question: A family has three children. What is the probability that the first is boy given that one is a girl?

Thank you for your help!
Click here to see answer by shree840(260)

Question 435552: Hi!

I have a probability question: Two buddies are meant to take an exam in the morning. Instead of studying and resting the night before, they go out to a local pub and have one drink too many. They oversleep their exam. They then go to the professor the next day with the following excuse.They explain that a friend out of town had an emergency and they needed to drive out to help.
On the way back, they claim a tire popped and they could not get back in time to take the exam. The professor allows the two to take the exam and writes a new exam for the students.He puts the two in different rooms. The exam has only one question with no partial credit.The question reads: "Which tire?" What is the probability that the students pass the exam?
Thank you for your help!
Click here to see answer by shree840(260)

Question 435571: A family has three children. What is the probability that the first is a boy given that one is a girl?
Click here to see answer by robertb(4012)

Question 435578: a package contains 12 batteries, 3 of which are defective. if 4 are selected randomly, find the probability of getting:
a) 0 defective batteries b) 1 defective battery c) 3 defective batteries

Click here to see answer by robertb(4012)

Question 435584: z is the standard normal random variable (with a mean 0 and standard deviation 1), and X is a normal random variable with mean and standard deviation.
a machine produced bolts with a mean diameter of 0.30 inches and a standard deviation of 0.01 inches. The diameters are approximately noramlly distributes. What is the probability that a randomly selected bolt will have a diameter greater than 0.32 inches.
(a) What is the probability that a randomly selected bolt has diameter greater than 0.32 inches?
b) In a box of 100 such bolts, how many do you expect to have a diameter greater than 0.32?

Click here to see answer by robertb(4012)

Question 435573: three cards are drawn from a deck without replacement. find the probabilities as a simple fraction .
a) all are jacks b) all are clubs c) all are red card
Click here to see answer by edjones(7569)

Question 435549: Hi!

I need help with a probability question: You have three bags. Bag 1 contains two red balls and 5 green balls. Bag 2 contains 5 red balls and 3 green balls. Bag three contains a red ball and a green ball. You roll a fair six sided die and pick a ball out of Bag 1 if the die lands on 1. You pick a ball out of Bag
2 if the die lands on 2, 3, or 4. You pick a ball out of Bag 3 if the die lands on 5 or 6. What is the probability that you pick a red ball?
Thank you for your help!
Click here to see answer by edjones(7569)

Question 435657: Angela usually rushes to make it to the bus stop to catch the school bus, and will often miss the bus if it is early. The bus comes early to Angela's top 28% of the time. what is the probability that the bus will come early to at least once during a 5 day school week?
Click here to see answer by robertb(4012)

Question 435679: a coin is tossed and a single number cube can be rolled. What is the probability that the coin shows heads and the number cube shows 4 or 5?

Click here to see answer by ewatrrr(10682)

Question 435658: The table shows the numbers of species in the united states listed as endangered or threatened as of sept, 2004. find (A) probability that a listed animal is a bird and (B) the probability that an endangered animal is a bird.
endangered threathened

Mammal 69 9
Birds 77 14
Reptile 14 22
amphibians 11 10
other 219 74
Click here to see answer by ewatrrr(10682)

Question 435687: A recent survey in Malaysia revealed that 60% of the vehicles traveling on highways, where speed limits are posted at 110 km per hour, we exceeding the limit. Suppose you randomly record the speeds of ten vehicles traveling on KL – Seremban highway where the speed limit is 110 km per hour. Let X denotes the number of vehicles that were exceeding the limit and follows a binomial distribution. Find the following probabilities:

a. P (X =10)
b. P (4 < x <9)
c. P (X = 2)
d. P (3 ≤ X ≤ 6)

Click here to see answer by ewatrrr(10682)

Question 435620: Scores on an English test are normally distrubuted with a mean of 33.8 and a standard deviation of 8.5. What score separates the top 59%, from the bottom 41%?
Click here to see answer by ewatrrr(10682)

Question 435801: A computer password consists of six characters. The first two must be lowercase letters and the remaining four can be either digits or lowercase letters. How many passwords are there which contain no repeated characters?
Click here to see answer by stanbon(57282)

Question 435798: How many four-digit numbers less than 6000 can be made using only odd digits?
Click here to see answer by stanbon(57282)

Question 435832: How many students of 3000 will have an IQ score less than 85 with a mean of 100 and standard deviation of 20?
Click here to see answer by ewatrrr(10682)

Question 435913: You roll two dice. What is the probability that the first lands on a 6 given that the sum is 10. So what I did is just 1/6*1/6= 1/36. Is that right?
Click here to see answer by stanbon(57282)

Question 435915: You roll two dice. What is the probability that the first lands on a 6 given that the sum is 10. So what I did is just 1/6*1/6= 1/36. Is that right?
Click here to see answer by stanbon(57282)

Question 435911: A family has three children. What is the probability that one is a boy given that one is a girl? What I did is
1/2 * 1/2*1. Is that right?
Click here to see answer by stanbon(57282)

Question 435919: You roll two dice. What is the probability that the first lands on a 6 given that the sum is 10. I got 1/6*1/6. Is that right?
Click here to see answer by stanbon(57282)

Question 436059: If university officials say that at least 70% of the voting student population support the fee increase, if the 95% confidence interval is [0.75, 0.85], what conclusion can be drawn based on a 95% level of confidence?
A. 70% is not in the interval, need to take another sample
B. 70% is not in the interval, so assume it will not be supported
C. 70% is below the interval, so assume it will be supported
D. Since this was not based on population, cannot make conclusion

Click here to see answer by stanbon(57282)

Question 436126: ANY HELP WILL BE GREATLY APPRECIATED
Three balls are selected at random without replacement from an urn containing four green balls and six red balls. Let the random variable X denote the number of green balls drawn.
a. List the outcomes of the experiment
b. Find the value assigned to each outcome of the experiment by the random variable X
c. Find the event comprising the outcomes to which a value of 3 has been assigned by X

Click here to see answer by edjones(7569)

Question 436119: The 2003 Zagat Restaurant Survey provides food, décor, and service ratings for some of the top restaurants
across the United States. For 15 top-ranked restaurants located in Boston, the average price of a dinner
including, one drink and tip, was $48.60. You are leaving for a business trip to Boston and will eat dinner at
three of these restaurants. Your company will reimburse you for a maximum of $50 per dinner. Business
associates familiar with these restaurants have told you that the meal cost at one-third of these restaurants
will exceed $50. Suppose that you randomly select three restaurants for dinner.

a. What is the probability that none of the meals will exceed the cost covered by your company?
b. What is the probability that one of the meals will exceed the cost covered by your company?
c. What is the probability that two of the meals will exceed the cost covered by your company?
d. What is the probability that all three of the meals will exceed the cost covered by your company?
Click here to see answer by edjones(7569)

Question 436101: From an ordinary deck of 52 cards, five are drawn randomly. What is the probability of drawing exactly three face cards?
Click here to see answer by edjones(7569)

Question 436097: Six fair dice are tossed. What is the probability that at least two of them show the same face?
Click here to see answer by edjones(7569)

Question 436112: How many "unique" ways can 10 people fit on a 4-person park bench?
Click here to see answer by edjones(7569)

Question 436099: Five boys and five girls sit at random in a row. What is the probability that the boys are together and the girls are together?
Click here to see answer by robertb(4012)

Question 436115: Your boss has determined that the number of people "x" who call in sick on Fridays approximates a Poisson distribution. She also notes that, for the past many years, the average number of employees absent on Friday is 2.6. Given this data she asks you to compute the probability that more than 5 will be sick on a given Friday.
Click here to see answer by robertb(4012)

Question 436102: A random sample of n elements is taken from a population of size N without replacement. What is the probability that a fixed element of the population is included? Simplify your answer.
Click here to see answer by robertb(4012)

Question 436054: A Math test has a mean of 49 and standard deviation of 10.0. Find the corresponding z scores for:

I. a test score of 62
II. a test score of 30
Click here to see answer by robertb(4012)

Question 436313: Find the probability of choosing each type of card combination at random from a standard deck of 52 cards if you replace the first card.
at least one of the two cards is a red face card
Click here to see answer by stanbon(57282)

Question 436310: A battery operated digital pressure monitor is being developed for use in calibrating pneumatic pressure gauges in the field. It is thought that 95% of the readings it gives lie within 0.01 lb/in^2 of the true reading. In a series of 100 tests, the gauge is subjected to a pressure of 10,000 lb/in^2. A test is considered to be a success if the reading lies withing 10,000 +/- lb/in^2. We want to tst Ho: p=.95 H1: p does not equal .95 at the alpha = .05 level.
A. What are the critical points for the test?
B. When the data are gathered, it is found that 98 of the 100 readings were successful. Can Ho be rejected at the alpha =.05 level? To what type error are you now subject?
THANK YOU in advance.

Click here to see answer by stanbon(57282)

Question 376426: An experiment is designed to investigate the impact of different positions of the mother on fetal heart rate. Fetal heart rate is measured by ultrasound in beats per minute. The study included 20 women who were assigned to one position and had the fetal heart rate measured in that position. Each woman was between 28 and 32 weeks gestation. The data are shown in table 7-47. Is there a significant difference in mean fetal heart rates by position? Run the test at a 5% level of significance.
Textbook Used: Sullivan, Lisa M. Essentials of Biostatistics in Public Health (2008).
Click here to see answer by donovan1(1)

Question 436362: Military radar and missile detection system are designed to warn a country of an enemy attack. A
reliability question is whether a detection system will be able to identify an attack and issue a warning.
Assume that a particular detection system has a .90 probability of detecting a missile attack.

a. What is the probability that single detection system will detect the attack?
b. If two detection systems are installed in the same area and operating independently, what is the
probability that at least one of the systems will detect the attack?
c. If three systems are installed, what is the probability that at least one of the systems will detect
the attack?
d. Would you recommend the multiple detection systems be used? Explain.

Click here to see answer by stanbon(57282)

Question 436238: Please show the formula(s) for question given.
Given a normal distribution with a mean of 85 and a sample standard deviation of 15, how much of the data should be in the interval between 55 and 115? Thank you.
Click here to see answer by stanbon(57282)

Question 436428: You are given 5 baseball cards numbered 1 to 5. You select a card,do not replace it,and select again. What is P(2,5)?
Click here to see answer by richard1234(5390)

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, 3871..3915, 3916..3960, 3961..4005, 4006..4050, 4051..4095, 4096..4140, 4141..4185, 4186..4230, 4231..4275, 4276..4320, 4321..4365, 4366..4410, 4411..4455, 4456..4500, 4501..4545, 4546..4590, 4591..4635, 4636..4680, 4681..4725, 4726..4770, 4771..4815, 4816..4860, 4861..4905, 4906..4950, 4951..4995, 4996..5040, 5041..5085, 5086..5130, 5131..5175, 5176..5220, 5221..5265, 5266..5310, 5311..5355, 5356..5400, 5401..5445, 5446..5490, 5491..5535, 5536..5580, 5581..5625, 5626..5670, 5671..5715, 5716..5760, 5761..5805, 5806..5850, 5851..5895, 5896..5940, 5941..5985, 5986..6030, 6031..6075, 6076..6120, 6121..6165, 6166..6210, 6211..6255, 6256..6300, 6301..6345, 6346..6390, 6391..6435, 6436..6480, 6481..6525, 6526..6570, 6571..6615, 6616..6660, 6661..6705, 6706..6750, 6751..6795, 6796..6840, 6841..6885, 6886..6930, 6931..6975, 6976..7020, 7021..7065, 7066..7110, 7111..7155, 7156..7200, 7201..7245, 7246..7290, 7291..7335, 7336..7380, 7381..7425, 7426..7470, 7471..7515, 7516..7560, 7561..7605, 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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17551..17595, 17596..17640, 17641..17685, 17686..17730, 17731..17775, 17776..17820, 17821..17865, 17866..17910, 17911..17955, 17956..18000, 18001..18045, 18046..18090, 18091..18135, 18136..18180, 18181..18225, 18226..18270, 18271..18315, 18316..18360, 18361..18405, 18406..18450, 18451..18495, 18496..18540, 18541..18585, 18586..18630, 18631..18675, 18676..18720, 18721..18765, 18766..18810, 18811..18855, 18856..18900, 18901..18945, 18946..18990, 18991..19035, 19036..19080, 19081..19125, 19126..19170, 19171..19215, 19216..19260, 19261..19305, 19306..19350, 19351..19395, 19396..19440, 19441..19485, 19486..19530, 19531..19575, 19576..19620, 19621..19665, 19666..19710, 19711..19755, 19756..19800, 19801..19845, 19846..19890, 19891..19935, 19936..19980, 19981..20025, 20026..20070, 20071..20115, 20116..20160, 20161..20205, 20206..20250, 20251..20295, 20296..20340, 20341..20385, 20386..20430, 20431..20475, 20476..20520, 20521..20565, 20566..20610, 20611..20655, 20656..20700, 20701..20745, 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