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Question 649537: a deck of cards numbered 1 through 32 what is the probability that the card drawn will be a factor of 5
Click here to see answer by solver91311(16885)

Question 649593: Among the 2,598,960 possible five-card poker hands from a standard 52-card deck, how many contain AT LEAST ONE CLUB (complement of "no clubs")?
Click here to see answer by ewatrrr(10682)

Question 649486: The following items are based on the summarized table below:
hours of study
1
2
3
5
ZX=11
score on the quiz
3
5
7
9
ZY=24
XY
3
10
21
45
ZXY79
Part A** Compute the Pearson correlation.
1.What is the covariance? I believe the answer is 4.33
2.What is the standard deviation of the predictor variable? I believe the answer is 1.73
3.What is the standard deviation of the criterion variable? I believe the answer is 2.58
4.What is the Pearson’s r value? I believe the answer is 0.97
Part B**Compute the regression equation.
5.What is the numeric value for the slope? I believe the answer is 1.45
6.What is the y-intercept?
7.Set up the regression equation and use to predict the total number of points on the quiz for a person studying 6 hours. The number of points predicted for a person studying 6 hours is?
Please help me!!! Thank you!

Click here to see answer by Kniteowl(1)

Question 650115: 20.2, 22.4, 30.0, 37.6, 39.8
True or False? These numbers can be used to calculate the standard deviation of the distribution.

Click here to see answer by ewatrrr(10682)

Question 650346: 16 out of 100 students eat ice cream at lunch. what decimal represents the number of students that eat ice cream?

Click here to see answer by josmiceli(9678)

Question 650424: If Jeannie has 8 shirts for every 5 pair of jeans how many jeans she has for 40 shirts
Click here to see answer by fcabanski(874)

Question 650701: 5. max went to the mcg to practice his cricket max has determined that his prob of hitting a 4 of any ball when playing cricket is 0.07 wat is the lowest number of balls he must face to ensure that the prob of hitting more than 4 4’s is more than 0.8.
A 4
B 15
C 45
d 65
e 95
B) explain why A could not correct

7.Continous random variable X has a pdf given by f(x)= -3x/4 (x-2) |0 The mode of X:
A 0
B 0.75
C 1
D 1.5
E 2
B) explain why A is not correct
C) If the mean was found instead of the mode, which answer would be correct.

8. Pr(X<.5|X<1), correct to 4 dp
A 0.0781
B 0.1563
C 0.1582
D 0.3125
E 0.3164
B) using a sketch graph, explain why A is not correct
C) Keeping the question conditional, vary the it so that A is the solution

9. after the formal, tiff was evaluating fashion sense, she gave them ratings out of 50, rating were normally distributed with a mean of 30 and a variance of 49, if tiff awarded the best 8% a A+, then her cut off score to the nearest interger, for an A+ would have been.
A 10
B 20
C 35
D 40
E 50
B) Using a sketch graph, explain why A is not correct
C) change the wording of the questionn so B is correct

10.The random variable X has a normal distribution with mean 10 and Standard dev. 2, the prob that X is less than 5 given that it is less than 10 is closest to.
A 0.0062
B 0.0124
C 0.4969
D 0.5000
E 0.9938
B) Using a sketch graph explain why D is not correct
C) What is error if A was selected.

11.Past months indicate that if it rains on a particular day there is an 80% chance that it will rain the next day. If it does not rain on a particular day, the probability that it will rain the next day is p%. It rained on Monday and the probability that it rained on the following Wednesday was 65%. The value of p is:
A 5
B 10
C 15
D 20
E 35
B) Alter the question by changing either the 80% or the 65% or both so that D is correct.

12.The prob mr.bettiol wins any game is 0.4, no game can be a draw, if the prob that mr.purcell wins no game is less than 0.01, then minimum number games they play is equal to.
A 5
B 6
C 7
D 9
E 10
B) Only change the prob of mr.bettiol winning a game from 0.4, so that answer E is correct.

13.if X is normally distributed random variable with mean, µ, and variance (9 µ^2)/4, then
Pr(X>2 µ) is closest to.
A 0.023
B 0.252
C 0.504
D 0.672
E 0.748
B) explain why E is not correct.

14.Normally distrubted with a mean of 45 minutes and a Standard dev. of 8 minutes, if Z is the random variable of the standard normal distribution, the prob that Kate travel is more than 55 minutes is equal to.
A Pr(Z<1.25)
B 1-Pr(Z<1.25)
C Pr(Z>-1.25)
D Pr(Z<2)
E 1-Pr(Z<2)
B) What is the error if A was selected
C) Change the question so that D is correct.

15.She only runs north or east. If she run north for 1 block, the prob she will turn east at the nearest intersection is 0.6. if she runs east for 1 block, the prob that she will turn north at the nearest intersection is 0.75. Anja begins running north for the first block, what is the prob she will turn north at the 5th intersection that she encounters.
A 0.44
B 0.45
C 0.55
D 0.56
E 0.66
B) if the question was long term rather 5th intersection, which solution is correct.

Click here to see answer by Aaniya(63)

Question 650680: A random sample of 1000 light bulbs shows that the mean life is 600 hours with a standard deviation of 50 hrs. If we know that the distribution is not normal, at least 89% of light bulbs will between which two amounts of ours.
They didn't gave me the k, and I don't know how to find it. Can you please help.
Click here to see answer by stanbon(57347)

Question 651431: if you are dealt 4 cards from a shuffled deck of 52 cards. Find the probability that all 4 cards are queens.
How do I solve this??
Click here to see answer by stanbon(57347)

Question 651499: The weights of trout in a certain river follow a normal distribution with mean 3 pounds and standard deviation 0.8 pounds. Fishermen must throw back any trout under the minimum weight of 2 pounds. What percent will be thrown back?
Click here to see answer by stanbon(57347)

Question 651419: there is a group consisting of 9 Democrats, 9 Repubicans and 2 Independents.
Suppose that 2 group members are selected at random and in succession.
Find the probability of selecting 2 independents.
Do I use nPr to solve with 20P2? Or how do I solve this?
Click here to see answer by stanbon(57347)

Question 651394: In a binomial distribution, n=7 and "30. Find the probabilities of the following events. (Round your answers to 4 decimal places.)

(a) x=2
B) x<2 underline <
c) x>3 underline >
Click here to see answer by stanbon(57347)

Question 651322: In a normal distribution 26% of the scores are below 40 and 7% are above 80. Find out the mean and standard deviation of the distribution?
Click here to see answer by stanbon(57347)

Question 651301: graces loves to eat salad how many salads can she put together if she can pick out one type of lettuce from 2 choices one vegetable from 4 choices and one dressing from 7 choices
Click here to see answer by stanbon(57347)

Question 651093: A policy requiring all hospitals to take lie detector tests may reduce losses due to theft, but some employees regard such tests as a violation of their rights. Reporting on a particular hospital that uses this procedure, the Orlando Sentinel Star (August 3, 1981) notes that lie detectors have accuracy rates that vary from 92% to 99%. To gain some insight into the risks that employees face when taking a lie detector test, suppose that the probability is .05 that a particular lie detector concludes that a person is lying who, in fact, is telling the truth, and suppose that any pair of tests are independent. What is the probability that a machine will conclude that each of the three employees is lying when all are telling the truth? What is the probability that the machine will conclude that at least one of the three employees is lying when all are telling the truth?
-This section of the book is about the multiplicative law of probability and the additive law of probability.
Click here to see answer by stanbon(57347)

Question 651553: Hello. Any help on this one is greatly appreciated.
Given that x is a normally distributed random variable with a mean of 28 and a standard deviation of 7, find the following probabilities:
P (x < 48)
Click here to see answer by stanbon(57347)

Question 651550: we are drawing two cards without replacement from a standard 52- card deck. find the probability of drawing at least one face card.
Click here to see answer by stanbon(57347)

Question 651548: Hello. Any help on the following is greatly appreciated.
Find the standard score (z) such that the area below the mean and below z is about 16% of the area under the normal curve.
Note: I've seen this answer z = invNorm(0.16) = -0.9945, however I'd like to understand the steps to get here. Thanks!
Click here to see answer by stanbon(57347)

Question 651587: Nine college students had eaten the following number of times at a fast food restaurant for dinner in the last ten days:
4,10,1,7,1,8,1,5,2.
Find the mean, median, mode, range, and midrange for these data. Please so ALL of your work.

Click here to see answer by MathLover1(6632)

Question 651636: A standard placement test has a mean of 125 and a standard deviation of 15. Determine the minimum sample size if we want to be 90% certain that we are within 3 points of the true mean.
Right now I have Za/2= 1.645 and the margin of error is where I am getting stuck. I have it up to the point of 16.45/sqr root of n=3. I think the next step is to figure out n by n=(16.45/3)^2= 30.06. I don't know where to go from there or if I am finished?
Click here to see answer by reviewermath(522)

Question 651584: PART I. Use Chebyshev's theorem to find what percent of the values will fall between 166 and 346 for a data set with a mean of 256 and standard deviation of 18.
Part II. Use the Empirical Rule to find what two values 95% of the data will fall between for a data set with a mean of 272 and standard deviation of 14.
Failure to show ALL work will result in loss of point!

Tutors.... I hope you can help me.
Click here to see answer by Theo(3464)

Question 651796:
A Travel Weekly International Air Transport Association survey asked business travelers about the purpose for their most recent business trip. 19% respond that it was for an internal company visit. Suppose 950 business travelers are randomly selected.

A: What is the probability that more than 25% of the business travelers say that reason for their most recent business trip was an internal company visit?

B: What is the probability that 15% and 20% of the business travelers say that the reason for their most recent business trip was an internal company visit?

C: What is the probability that between 133 and 171 of the business travelers say that the reason for their business trip was an internal company visit?

Click here to see answer by stanbon(57347)

Question 651766: A coin is tossed 56 times. Find the standard deviation for the number of heads that will be tossed.

Click here to see answer by stanbon(57347)

Question 651756: What is standard normal variable? Why do we normal variable convert into standard normal variable? Explain
Please answer this, thanks.
Click here to see answer by stanbon(57347)

Question 652210: Find the area under the normal distribution curve to the right of z = –3.24.
Click here to see answer by jim_thompson5910(28595)

Question 652555: I have three pumps, Pump A,B, and C. The pumps run for exactly 20 mins per hour, every hour. What is the probability that at any given hour of the day, all three pumps will be running at the same time?
Click here to see answer by Edwin McCravy(8909)

Question 652623: The FBI claims that about 80% of all property crimes, the criminals are never found and the case is never solved. In a randomly selected city, what is the probability that at least 1 crime will be solved when 6 crimes are reported?
I need help setting up the formulas
Click here to see answer by stanbon(57347)

Question 652628: The credit card industry has determined that about 65% of college students will be late making a minimum payment when paying their credit card every year at least once. If 10 randomly selected students who own a credit card is selected.

What is the probability that at most 2 of the ten selected are late with their credit card payment?

What is the probability that more than 7 are late with their credit card payment?
I need help with which formula to use and how to set up the problem

Click here to see answer by ewatrrr(10682)

Question 652883: If two different students are randomly selected from a class of 12 boys and 8 girls, what is the probability that both students are girls. (express your answer as a common fraction.) show all work
Click here to see answer by stanbon(57347)

Question 652906: The scores of 12,17,15 and x have a value of 13. What is the value of x?
Click here to see answer by rfer(12660)

Question 653038: Suppose five items are selected randomly from a production line that is known to produce defective items 5% of the time. What is the probability of getting exactly two defective items?
Click here to see answer by Shana-D77(122)

Question 653184: 320 statistics and probability a bag contains 5 red balls and 3 green balls. a ball is drawn and then replaced before a ball is drawn again. draw a tree diagram to show all the possible outcomes. find the probability that two green balls are drawn
Click here to see answer by rfer(12660)

Question 653324: The percentage of the general population that has each blood type is shown in the table below. Determine the probability distribution associated with these data. (Enter your answers to two decimal places.)
Blood Type A B AB O
Population, % 44 14 3 39
Probability ? ? ? ?
Click here to see answer by stanbon(57347)

Question 653323: the senate in a certain state is comprised of 60 republicans, 39 democrats, and 1 independent.How many committees can be formed if each committee must have 3 republicans and 2 democrats?
Click here to see answer by stanbon(57347)

Question 653320: A $20 bill, two $10 bills, three $5 bills and four $1 bills are placed in a bag. If a bill is chosen at random, what is the expected value for the amount chosen?
Click here to see answer by stanbon(57347)

Question 653302: you are ordering ice cream and have a choice of 3 toppings. you can have any or all the toppings. what are your possible choices? 4 toppings hoe many choices. n toppings? how many possibilities would you have
Click here to see answer by stanbon(57347)

Question 653249: If we roll two dice 180 times, how many times can we expect the dice to show a sum of five?

Click here to see answer by stanbon(57347)

Question 653278: Suppose that P(A) = 0.66, P(B) = 0.56 and P(AB) = 0.37.
Find the conditional probability that B occurs given that A occurs.
Round your answer to 3 decimal places.
Click here to see answer by Edwin McCravy(8909)

Question 653022: You have a coin which is loaded so that the probability of tossing heads is 0.45. If you toss the coin three times, what is the probability that you will obtain three tails? Round your answer correct to three decimal places.
Click here to see answer by stanbon(57347)

Question 653012: for a normal population mean of 70 and population standard deviation of 20, what is the probability of obtaining a sample mean equal to or greater than 75 for a random sample of n= 100?

for a normal population mean of 70 and population standard deviation of 20, what is the probability of obtaining a sample mean equal to or greater than 75 for a random sample of n= 50?
Please help me solve these
dbmoody@yahoo.com
Click here to see answer by stanbon(57347)

Question 653584: A bag contains 7 blue marbles, 8 green marbles, 15 red marbles, and 10 yellow marbles. Find the probability of randomly drawing without replacement, a blue marble and then a red.
Click here to see answer by stanbon(57347)

Question 653592: Most software manufactures offer a free help line that allows customers to call an 800 number to receive assistance with their problems. Because of the volume of calls, often customers are put on hold. Greeting Card Art, Inc. is proud of the fact that 93 percent of their calls for assistance are answered directly by a technician who can solve the customer's problem. To monitor this service claim, suppose Greeting Card Art selects a random sample of 25 recent calls.
A. Explain why this situation fits a binomial distribution.
B. What is the probability exactly 20 of the calls are answered directly by a technician?
C. What is the probability at least one of the calls is put on hold?
Click here to see answer by stanbon(57347)

Question 653608: How many green blocks should be added to a bag that holds 1 blue block and 3 yellow blocks to make the probability of randomly selecting a green block from the bag equal to 1/2?
Click here to see answer by stanbon(57347)

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