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Question 253808: The probability that Robin Hood hits a target is 5/6. The probability that Little John hits a target is 1/7. If Robin Hood and Little John each shoot one arrow at the target, what is the probability that they both miss
Click here to see answer by palanisamy(496)

Question 253866: I am completely lost on this one, any help would be appreciated!
According to J.D. Power and Associates, the mean defect rate in a new 2004 Porsche was 2.4. In a randomly selected new Porsche, find the probability of (a) at least one defect; (b) no defects; (c) more than three defects. (d) Construct the probability distribution (Excel or Appendix B), make a graph of its PDF, and describe its shape. (Data are from TheWall Street Journal, June 30, 2004, p. D3.)
Click here to see answer by stanbon(57361)

Question 253864: On the midnight shift, the number of patients with head trauma in an emergency room has the probability distribution shown below. (a) Calculate the mean and standard deviation.
x 0 1 2 3 4 5 Total
P(x) .05 .30 .25 .20 .15 .05 1.00
Is there a way to enter this data in Excel to calculate mean and std. deviation?
Thank you!
Click here to see answer by stanbon(57361)

Question 254025: a bag contains 20 red marbles, 16 green marbles, and 12 blue marbles. If you select one marble at random form the bah, what is the probability that the marble is green?
Click here to see answer by stanbon(57361)

Question 254101: A quality control engineer is interested in the mean length of sheet insulation being cut automatically by machine. The desired length of insulation is 12 metres. It is known that the standard deviation in the cutting length is 0.15 metres. A sample of 144 cut sheets yield a mean length of 12.14 metres. This sample will be used to obtain a 90% confidence interval for the mean length cut by machine.
What are the two limits of the confidence interval? Min and max?
Click here to see answer by stanbon(57361)

Question 254218: Six cups and saucers come in pairs: there are two cups and saucers which are red, two white, and two with stars on. If the cups are placed randomly onto the saucers (one each), find the probability
that no cup is upon a saucer of the same pattern.
Click here to see answer by Edwin McCravy(8909)

Question 254100: What would be your decision if a hypothesis test was conducted on this problem with the null hypothesis given as H0 : u more or equals to 2 and the alternate hypothesis given as H1 < 2.
a. reject H0 at the 10%, 5% and 1% level of significance
b. reject H0 at the 10% and 5% level of significance but do not reject H0 at the 1% level of significance
c. reject H0 at the 10% level of significance but do not reject H0 at the 5% or 1% level of significance
d. Do not reject H0 at either 10%, 5% or 1% level of significance.
Click here to see answer by stanbon(57361)

Question 254099: true or false: supposed, in testing a hypothesis about a porportionn, the p-value is computed to be 0.034. the null hypothesis should be rejected if the chosen level of significane is 0.01
Click here to see answer by stanbon(57361)

Question 254039: list the sample space if u roll the number cube once?
Click here to see answer by stanbon(57361)

Question 253978: Given the following sample data of head injury to crash test dummies and a significance level of α = 0.05, test the claim
that the four samples come from populations with the same mean (μ1 = μ2 = μ3 = μ4).

Subcompact Cars Compact Cars Midsize Cars Full-Size Cars
681 643 469 384
428 655 727 656
917 442 525 602
898 514 454 687
420 525
259 360

a. What is the sum of squares between groups?
b. What is the sum of squares within groups?
c. What is the degrees of freedom between groups?
d. What is the degrees of freedom within groups?
e. What is the F value?
f. What is the Fcritical value?
g. What is the p-value?
h. Based on the p-value describe why you accept/reject the hypothesis.

Click here to see answer by stanbon(57361)

Question 254321: A number from 22 to 28 is drawn at random p(not a 28)
Click here to see answer by drk(1908)

Question 254320: A number from 11 to 18 is drawn at random P (an odd number)
Click here to see answer by stanbon(57361)

Question 254320: A number from 11 to 18 is drawn at random P (an odd number)
Click here to see answer by rfer(12662)

Question 254444: I’m throwing 8 dice up in the air. What’s the probability that half land on an even number, while the other half land on 1?
Click here to see answer by palanisamy(496)

Question 254451: Smith Widget Company makes widgets for the medical industry. One particular customer requires widgets that meet FDA standards. One FDA standard requires Z-testing of at least 100 widgets at a time at the .08 level of significance. The specific standard requires that widgets be no smaller than a certain tolerance and no larger than a certain tolerance. The critical value(s) for such a test would be: __________
Based on my calculation the z value would be -1.7597 for a 2-tail test. Can you confirm whether this is correct?
Click here to see answer by stanbon(57361)

Question 254450: A production manager is conducting a Z test of her assembly line. She collects a sample of 64 items from the assembly line and determines that the test’s critical value is +1.96 and the Z statistic is +1.73. Based on this information she should (circle one): Accept Reject the Null hypothesis.
I think you would accept the null hypothesis.
Click here to see answer by stanbon(57361)

Question 254409: YOU ROLL A BLUE NUMBER CUBE AND A GREEN NUMBER CUBE. FIND EACH PROBABILITY.

Question: p(blue 1 and green 1 or 2)

Click here to see answer by stanbon(57361)

Question 254461: a bag contains 4 white ball,5 red ball,6 green balls 3 balls are drawns at random.wht is the probabilty that a white ,ared ,gerrn ball is drawn
Click here to see answer by richwmiller(9143)

Question 254407: please help me
get the integral of sin(x-sin7x)dx
Click here to see answer by stanbon(57361)

Question 254627: A test shows that 10 out of 100 gadgets are defective. In a random sample of two gadgets are chosen, the probability that both are defective is:
A 1/1000
B 1/110
C 1/11
D 1/10
Help!
Click here to see answer by drk(1908)

Question 254560: Select the GCF of these numbers.
48 and 60

Click here to see answer by Alan3354(30993)

Question 254558: Select the GCF of these numbers. 25 · 5· 11 and 23· 52 · 7
Click here to see answer by Alan3354(30993)

Question 254558: Select the GCF of these numbers. 25 · 5· 11 and 23· 52 · 7
Click here to see answer by stanbon(57361)

Question 254558: Select the GCF of these numbers. 25 · 5· 11 and 23· 52 · 7
Click here to see answer by drk(1908)

Question 254677: you have an equally likely chance of choosing any integer from the set {1,2,3,4,5,6,7,8,9,10,11,12}. find the probability of the given event: A) an even number is chosen, B) a multiple of three is chosen, C) a prime number is chosen, D) a two digit number is chosen.
Click here to see answer by drk(1908)

Question 254694: A bag contains 3 red marables and 5 purple marables. One marable is drawn at random and not replaced. Then a second marable is drawn at random. What is the probability that the first marable is purple and the second one is red
Click here to see answer by richwmiller(9143)

Question 254695: A bag contains 7 red balls numbered 1,2,4,5,6,7 and 3 white balls numbered 3,8,9. If a ball is drawn at random, what is the probability the ball is:
A. red or odd numbered?
B. white or even numbered>
Click here to see answer by drk(1908)

Question 254698: Of a class of 25 students, 18 have brown eyes. If 2 students are chosen at random, what is the probability that both students have brown eyes.
Click here to see answer by edjones(7569)

Question 254760: Bob spins 2 spinners; one of which is labelled 1, 2, 3, and the other is labelled A, B, C and D.
Given that all the outcomes are equally likely, find the probability that:
a) the spinner stops at "2" and "C"
b) the spinner stops at "3" and either "B" or "D"
c) the spinners stop at "A" and any number
Click here to see answer by stanbon(57361)

Question 254808: International Pictures is trying to decide how to distribute its new movie ‘Claws’. ‘Claws’ is the story of an animal husbandry experiment at the University of Southern Queensland that goes astray, with tragic results. An effort to breed meatier chickens somehow produces an intelligent, 200 kilogram chicken that escapes from the lab and terrorises the campus. In a surprise ending the chicken is befriended by coach Tim Galvano, who teaches it how to play Rugby and help his team win State, National and World Championships. Because of the movie’s controversial nature, it has the potential to be either a smash hit, a modest success, or a total bomb. International is trying to decide whether to release the picture for general distribution initially or to start out with a ‘limited first-run release’ at a few selected theatres, followed by general distribution after 3 months. The company has estimated the following probabilities and conditional profits for ‘Claws’:
PROFITS (Millions of $)
Level of success, Probability, Limited release General distribution,
Smash, .3, 22, 12
Modest, .4, 9, 8
Bomb, .3, –10, –2

International can run sneak previews of ‘Claws’ to get a better idea of the movies’ ultimate level of success. Preview audiences rate movies as either good or excellent. On the basis of past experiences, it was found that 90% of all smash successes were rated excellent (and 10% rated good), 75% of all modest successes were rated excellent (25% rated good) and 40% of all bombs were rated excellent (60% rated good). The cost of running sneak previews is not cheap. Currently, this stands at $1m.
QUESTION a
What is the opportunity loss for a General Distribution for a Smash level of success?

QUESTION b
What would the optimal action be for International before running the sneak preview?
Run a limited release with an expected payoff of $7.20m
Run a limited release with an expected payoff of $6.20m
Run a general distribution with an expected payoff of $7.20m
Run a general distribution with an expected payoff of $6.20m
QUESTION c
What is the maximum amount of money that International would be prepared to pay for an absolutely reliable forecast of the movies’ level of success?
$9.6m
$7.2m
$6.2m
$2.4m
QUESTION d
What would be the joint probability for a ‘smash success’ and excellent preview given that in the past, it was found that 90% of all smash successes were rated excellent?
QUESTION e
What is the posterior probability of a smash success given the sneak preview indicates excellent?
QUESTION f
What is the maximum amount that should be paid for the sneak preview (i.e. what would be the expected value of sample information (EVSI))? Select the closest correct answer.
$1.04 million
$2.58 million
$7.2 million
$8.24 million
Click here to see answer by motusand(1)

Question 254807: An insurance company wishes to examine the relationship between income (in $,000) and the amount of life insurance (in $,000) held by families. The company drew a simple random sample of families and obtained the following results:
(Family) (Income) (Amount of life insurance)
A, 80, 120
B, 100, 200
C, 110, 220
D, 90, 160
E, 80, 180
F, 140, 270
G, 110, 150
H, 100, 240
I, 80, 160
J, 100, 210

QUESTION a
What is the least squares estimate of the slope?
Answer should be to four decimal places e.g. 1.2345.
QUESTION b
What is the least squares estimate of the Y intercept?
Answer should be to four decimal places e.g. 1.2345.
QUESTION c
What is the prediction for the amount of life insurance for a family whose income is $85,000?
QUESTION d
What would be the residual (error) term for a family income of $90,000?
Click here to see answer by stanbon(57361)

Question 254859: A single die is tossed eleven times. Find the probability that exactly five of the tosses show a "one".
Click here to see answer by stanbon(57361)

Question 254691: 2 cards are randomly selected from a 52-card deck. What is the probability of getting 2 hearts, or 2 numbers less then 8 (count aces as 1).
Click here to see answer by Fombitz(13828)

Question 254875: Nine customers at a supermarket are asked if they use brand X laundry soap. In general, 22% of the population use this brand. What is the probability that among the nine, more than two people use brand X? (round answer to 4 decimal places).
I keep getting impossible answers so I'm not sure if I'm setting the problem up wrong, or calculating it wrong.
Click here to see answer by scott8148(6628)

Question 254801: In a local cellular phone area, company A accounts for 70% of the cellular phone market, while company B accounts for the remaining 30% if the market. Of the cellular calls made with company A, 2% of the calls will have some sort of interference, while 3% of the cellular calls with company B will have interference.
Given that the randomly selected cellular calls is one that has interference, what is the probability it came from company B?
Click here to see answer by scott8148(6628)

Question 254870: C(8,0)*(.6^0)*(.4^8)
Does that equal 0?
Click here to see answer by stanbon(57361)

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, 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, 20746..20790, 20791..20835, 20836..20880, 20881..20925, 20926..20970, 20971..21015, 21016..21060, 21061..21105, 21106..21150, 21151..21195, 21196..21240, 21241..21285