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Question 31005: The IT department runs 3 redundant computer servers concurrently. For each server there is a 14% chance of crashing in a given day. Assume that a server crashing is independent from any other server crashing.
a) What is the probability that none of the 3 servers will crash for 7 consecutive days.
b) What is the probability that at least one server will crash in a seven day period?
c) What is the probability of a full network outage (all three servers going) in a given day?
I don't even know where to start with this question. Every time I try something the answer seems ridiculous. Any help would be appreciated.
Click here to see answer by venugopalramana(3286)

Question 31071: in a building, 120 people work on the second floor, 80 people work on the 3rd floor, and 100 people work on the 4th floor. if 20 people stepped into the elevator on the ground floor on their way to work, how many would you expect to get out on the second floor? answer: a:8.... b:9.....c:10.....d:12....
Click here to see answer by checkley71(8403)

Question 31087: Thirteen people are entered in a race. If there are no ties, in how many ways can the first two places come out?
Click here to see answer by venugopalramana(3286)

Question 31208: Consider being dealt 7 cards from a standard deck of 52. What is the probability that you will have exactly 4 spades?
Click here to see answer by venugopalramana(3286)

Question 31205: Consider being dealt 7 cards from a standard deck of 52. What is the probability that you will have at least on heart?
Click here to see answer by venugopalramana(3286)

Question 31206: In any classroom, there is a 92% chance that a randomly selected student will ask to go to the bathroom or go to the nurse. If the probability that he or she will ask to go to the bathroom is 80%, what is the probability that he or she will ask to go to the nurse? Assume independence.
Click here to see answer by venugopalramana(3286)

Question 31199: The probability of finding a parking space in a certain parking lot is 0.3. If four cars pull into the parking lot, what is the probability that of those four, 3 students will not find a spot? Assume independence.
Click here to see answer by venugopalramana(3286)

Question 31328: I need help on practical questions relating to chi-squared distribution:-
60 male and 50 female students at school. Each had to choose after-school activity from football,tennis,badmington and athletics. 25 males and 10 females picked football, only 3 males decided on tennis and 14 for badmington. Rest of males chose athletics along with 30 females. Remainder of females chose tennis and badminton in equal measure.
a)write down observed and expected frequency tables
b)write down null and alternative hypothesis to test wether sex and activity related
c)carry out chi squared distribution test at 5% significance level to test above hypothesis
Click here to see answer by stanbon(57239)

Question 31480: Suppose that the surface of the earth is smooth and spherical and that the distance around the equator is 25,000 miles. A steel band is made to fit snugly around the earth at the equator, then the band is cut and a piece of band 18 feet long is inserted. What will the gap be, all the way around, between the band and the earth's surface? (Round to three decimal places) (One mile=5280 feet) ((Please explain your work and answer at an algebra 2 level! Thanks again! :-P ))

Click here to see answer by Earlsdon(6287)

Question 31445: ) Bag 1 contains 12 green marbles, 5 blue marbles, and 3 yellow marbles. Bag 2 contains 8 blue marbles and 2 red marbles. I take two marbles at random from bag 2 and place them in bag 1. Then, I grab a random marble from bag 1. What is the probability that it is blue?
Click here to see answer by checkley71(8403)

Question 31455: A drawer has red socks and black socks. You take two socks out at random and the probability that both are red is exactly 1/2. How many socks are in the drawer?
Click here to see answer by checkley71(8403)

Question 31576: What is an outlier
Click here to see answer by stanbon(57239)

Question 31578: Draw a tree diagram to represent the outcomes of tossing a coin followed by rolling a single die. What is the probability of tossing heads and then rolling a 2.
Click here to see answer by stanbon(57239)

Question 31493: Eighteen guests have to be seated,half on each side of a long table.If four particular guests desire to sit on one
particular side and three others on the other side,the number of ways in which the sitting arrangement can be made is
A.11C5*9!*9!
B.11C6*8!*10!
C.11C5*8!*10!
D.None of the above
Click here to see answer by venugopalramana(3286)

Question 31446: 3) A regular hexagon is inscribed in a circle with circumference of 16π. A second circle is inscribed inside the hexagon. If you pick a point at random inside the larger circle, what is the probability that the point is also in the area of the smaller circle?
Click here to see answer by venugopalramana(3286)

Question 31638: 50% of American population is overweight.
65% of American population develops heart disease
57% of those overweight get heart disease
What is the probability of being overweight or having heart disease.
Click here to see answer by mbarugel(146)

Question 31852: Write the entire row of Pascal's triangle in which (8 choose 4) appears.

Click here to see answer by stanbon(57239)

Question 31991: Flip 2 coins 40 times and record your results in a table that lists the frequency of each outcome: HH, HT, TH and TT. Use your table to find the experimental probabilities of HH and TT.
Click here to see answer by stanbon(57239)

Question 32283: How many 26-letter arrangemenst of the alphabet have no two vowels together?
Click here to see answer by venugopalramana(3286)

Question 32346: Can you help me with this problem? Two cards are drawn from a standard deck of cards. Find the probability.
P(1 heart, 1 club)
Click here to see answer by stanbon(57239)

Question 32580: If x/y=4/7 and y/z=14/3.What is the value of [x+y]/z? could you solve this?
Click here to see answer by mukhopadhyay(490)

Question 32641: In North Dakota, most license plates consist of five lettes. How many different license plates are there if the letters can be repeated?
Click here to see answer by stanbon(57239)

Question 32807: I am unsure of how to answer this question at all. I have used the school's online system and have gotten nowhere.
The question is: The probability that San Francisco plays in the next Super bowl is nine times the probability that they do not play in the next Super Bowl. The probability that San Francisco plays in the next Super Bowl plus the probability that they do not play is 1. What is the probability that San Franscisco plays in the next super bowl?
I tried setting it up like this: 9(x) and
9+x=1
Click here to see answer by Earlsdon(6287)

Question 32804: A box contains 35 machine parts, 8 of which are defective. A quality control inspector randomly selects 5 of the 35 parts for testing. What is the probablility that at least one part is defective?
Click here to see answer by longjonsilver(2297)

Question 32968: Jim is playing blackjack his first card is a ten card. How does this affect the chance of getting 21 on his next draw? How does knowing the first card affect the second?
Click here to see answer by stanbon(57239)

Question 33051: I've tried working this but i'm pretty sure I am really wrong!
A drug company had previously reported that 1% of patients have a negative reaction to drug X. After the drug hits the market concerns are raised that the actual probability of a negative reaction is higher than the drug company reported. In an investegatory trial 500 patients are given the drug and 9 have a negative reaction.
a) what would be the expected number of negative reactions in the study of 500 patients given the drug company's rate is correct? .01* 500=5
b) What would be the variance of negative reactions in this study of 500 patients given that the drug company's rate is correct? I have no idea!
c) How likely would observing 9 negative reactions in 500 patients have been given the drug company's intial claim was correct. I'm not sure how to type in what I did but i'll try (500!/9!)*.01^9*.99^491. my answer is .035 which means very unlikely.
d) How likely would observing 1 negative reaction in 500 patients have been given the drug company's initial claim was correct? I did the same sort of thing (500!/1!)*.01^1*.99^499=.033.
e) How likely would it be to observe 9 or more negative reactions. The answer is the same as part c.
Any help is greatly appreciated!
Click here to see answer by stanbon(57239)

Question 33107: Consider a line segment AB with midpoint O.
Let X be any point on the line segment AB.
What is the probability that the line segmant's AX,XB and AO will make a traingle?
Click here to see answer by longjonsilver(2297)

Question 33305: If A and B are mutually exclusive events and P(A) = 0.3 and P(B) =0.2 find the following: a. P(A and B) do i just do .2+.3=.5 or is that wrong? i have no idea! and also b. P(A orB) is that just to divide or subtract? i am so... confused :/
Click here to see answer by mukhopadhyay(490)

Question 33307: ok, i dont get this one...
If a number cube is rolled 4 times, find the probability that an even number is rolled all 4 times. Thank you so much if you help me i am not very good at math...
Click here to see answer by stanbon(57239)

Question 33303: All of the sections on a circular spinner with 5 equal sections. If the spinner is spun 3 times, what is the probability that an even number is spun all 3 times?
Click here to see answer by stanbon(57239)

Question 33384: use multiplication the total numberof possible outcomes when spinning a spinner with the number 1 to 8 and a spinner with the letters a & b
Click here to see answer by stanbon(57239)

Question 33549: The age distribution of students at a community college is given below:
Number of students under 21: 416
Number of students 21-25: 402
Number of students 26-30: 210
Number of students 31-35: 55
Number of students over 35: 24
Total number of students: 1107
A student from the college is selected at random. Find the probability that the student is between 26 and 35 inclusive (meaning 26 and 35 year-olds should be included).
Click here to see answer by Cintchr(481)

Question 33551: If the probability that it will snow on Christmas in Burlington, Vermont is 0.8, what is the probability that it will NOT snow?
Click here to see answer by priya(51)

Question 33545: If it has been determined that the probability of an earthquake occurring on a certain day in a certain area is 0.03125, what are the odds AGAINST an earthquake?
Click here to see answer by priya(51)

Question 33550: A single fair die is rolled. What is the probability that the result is odd OR less than 5?
Click here to see answer by checkley71(8403)

Question 33564: A math teacher is randomly distributing 15 rulers with centimeter laables and 10 rulers without centimeter labels. What is the probability that the first ruler she hands out will have centimeter labels and the second ruler will not have labels?
Click here to see answer by venugopalramana(3286)

Question 33548: A fair die is rolled. What is the probability of rolling an even number?
Click here to see answer by venugopalramana(3286)

Question 33547: Two distinct even numbers are selected at random from the first ten even numbers greater than zero. What is the probability that the sum is 30?
Click here to see answer by venugopalramana(3286)

Question 33546: The table below shows the number of college students who prefer a given pizza topping:
Freshman: Cheese 12, Meat 25, Veggie 10
Sophomore: Cheese 10, Meat 21, Veggie 12
Junior: Cheese 20, Meat 10, Veggie 25
Senior: Cheese 21, Meat 12, Veggie 21
Find the empirical probability that a randomly selected student prefers cheese toppings.
Click here to see answer by venugopalramana(3286)

Question 33621: If it has been determined that the probability of an earthquake occurring on a certain day in a certain area is 0.03125, what are the odds AGAINST an earthquake?
The answer needs to be in ratio form i.e. 2 to 1 etc.
Click here to see answer by venugopalramana(3286)

Question 33640: IF THREE RADIOS OUT OF 75 ARE FOUND DEFECTIVE WHAT IS THE PROBABILTYY OF GETTING A DEFECTIVE RADIO
WOULD YOu DO 75 divide by 3

2. find the lateral area of a cylinder 15 in tall with a 6 in dimater
find the volume of a cube with a side 3.2 cm
this one i am stuck on
Click here to see answer by Nate(3500)

Question 33622: If it has been determined that the probability of an earthquake occurring on a certain day in a certain area is 0.03125, what are the odds AGAINST an earthquake?
Answer should be in ratio form.
Click here to see answer by mszlmb(115)

Question 31453: An elevator containing 5 people can stop at any one of 7 floors. What is the probability that no 2 people get off on the same floor? (Assume each floor is equally like for each person)
Click here to see answer by venugopalramana(3286)

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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, 14356..14400, 14401..14445, 14446..14490, 14491..14535, 14536..14580, 14581..14625, 14626..14670, 14671..14715, 14716..14760, 14761..14805, 14806..14850, 14851..14895, 14896..14940, 14941..14985, 14986..15030, 15031..15075, 15076..15120, 15121..15165, 15166..15210, 15211..15255, 15256..15300, 15301..15345, 15346..15390, 15391..15435, 15436..15480, 15481..15525, 15526..15570, 15571..15615, 15616..15660, 15661..15705, 15706..15750, 15751..15795, 15796..15840, 15841..15885, 15886..15930, 15931..15975, 15976..16020, 16021..16065, 16066..16110, 16111..16155, 16156..16200, 16201..16245, 16246..16290, 16291..16335, 16336..16380, 16381..16425, 16426..16470, 16471..16515, 16516..16560, 16561..16605, 16606..16650, 16651..16695, 16696..16740, 16741..16785, 16786..16830, 16831..16875, 16876..16920, 16921..16965, 16966..17010, 17011..17055, 17056..17100, 17101..17145, 17146..17190, 17191..17235, 17236..17280, 17281..17325, 17326..17370, 17371..17415, 17416..17460, 17461..17505, 17506..17550, 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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