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Question 235071: Find the area under the standard normal curve between z = -1.53 and z = 0. Round the answer to 4 decimal places.
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Question 236066: A card is drawn from an ordinary deck of 52 cards, and the result is recorded on paper. The card is then returned to the deck and another card is drawn and recorded. Find the probability that the following occurs.
Only the first card is a club
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Question 236105: Three coins are tossed in the air. what is the probability that exactly two of them turn up heads?
{hhh, hht, hth, htt, thh, tht, tth, ttt}
Exactly 2 heads ==> {hht, hth, thh}
P(exactly 2 heads) = 3/8.
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Question 236064: A card is drawn from an ordinary deck of 52 cards, and the result is recorded on paper. The card is then returned to the deck and another card is drawn and recorded. Find the probability that the following occurs.
Only the first card is a club
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Question 236112: In a local college, 60% of the math majors are women. Fifteen math majors are chosen at random. (1 points each)
a. What is the probability that exactly 6 are women?

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Question 236120: a manufacturer purchases two machines A and B .the probability that A will last five years is 4/5 and the probability that B will last five years is 3/4 find the probability that atleast one machine will last for five years
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Question 236189: Find the mean, variance, and standard deviation of n=90, p=0.2
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Question 236227: 6. Dewey, Cheetum, and Howe is a law firm that handles divorce cases. A previous study showed that in 34% of the time, their client got everything that was requested in the initial divorce papers. How many divorce proceedings would they have to survey to construct a 99% confidence interval for the true proportion of their clients get everything that they wanted in the divorce? If this interval is high enough, it would be a great advertising piece of information.
I have no idea where to start please help me.
Click here to see answer by stanbon(57967)

Question 236368: An insurance company has discovered that only about 0.1% of the population is involved in a certain type of accident each year. If its 10000 policy holders were randomly selected from the population, what is the probability that not more than 5 of its clients are involved in such an accident next year?
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Question 236467: The State of Pennsylvania has changed one of its toll roads from manual collection of tolls to machine collection. The idea behind the change was to allow traffic to flow more quickly through the toll plaza. With human attendants, the mean number of cars passing through the toll plaza was 1,253 per hour. A random sample of 120 hours under the new machine system of toll collection shows a sample mean of 1,261 with a standard deviation of 59. Should Pennsylvania adopt the new system for all toll roads in the state?
Using the 7 steps in significance testing as outlined in Lecture 9, perform the z test for each question below. Show all 7 steps and state your conclusion
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Question 236506: I can't figure out how to set the problem up. Can you please help? Thanks for all your help.

The pulse rates below were recorded over a 30-second time period, both before and after a physical fitness regimen. The data is shown below for 8 randomly selected participants. Is there sufficient evidence to conclude that a significant amount of improvement took place? Assume pulse rates are normally distributed. Test using = 0.10.
· State the null and alternate hypotheses
· Calculate the mean and standard deviation
· Determine which test statistic applies, and calculate it
· Determine the critical value(s).
· State your decision: Should the null hypothesis be rejected?
Before 56 38 56 33 38 51 57 55
After 56 38 64 37 43 55 63 61

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Question 236507: You are given the following data. Test the claim that there is a difference in the means of the two groups. Use = 0.01.
Group A Group B
x1= 7 x2 = 10
s1= 12 s2 = 11
n1= 66 n1 = 92
· State the null and alternate hypotheses
· Determine which test statistic applies, and calculate it
· Determine the critical value(s).
· State your decision: Should the null hypothesis be rejected?
Click here to see answer by stanbon(57967)

Question 236504: A machine produces 9 inch latex gloves. A sample of 69 gloves is selected, and it is found that 45 are shorter than they should be. Find the 98% confidence interval on the proportion of all such gloves that are shorter than 9 inches.
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Question 236798: A bag contains 6 red marbles and 4 green marbles. I reach in the bag and draw out two marbles at the same time. What is the probability that they are both red?
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Question 236785: if you roll a fair die, what is the probability that you will observe a number greater than 4?
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Question 236859:
9 balls numbered 1 to 9, two balls are chosen at random. Find the probability that the number on both balls are odd.
5/9 * 4/8 = 5/18
Click here to see answer by edjones(7569)

Question 236808: The letters of the word Mississippi are placed in a hat. What is the probability that the first two letters drawn are both i if the first letter drawn is not replaced?
Click here to see answer by Alan3354(31518)

Question 236839: In a certain company, 120 of the employees are men. What is the total number of employees if 5 out of every 8 employees are men?
Can somebody please solve this sum and explain how you got to the answer?
Thanks
Click here to see answer by rfer(12730)

Question 236927: What is the probability that it will rain 2 of the next 10 days when the probability of rain is 90%? Show the formula and your calculations.
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Question 236924: What is the probability that it will rain 7 of the next 9 days whent he probability of rain is 80%? Show the formula and your calculations.
Click here to see answer by solver91311(17077)

Question 237144: when an event is certain to occur, what is its probabiliti?
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Question 237144: when an event is certain to occur, what is its probabiliti?
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Question 237074: 1,2,3,4,5 and 6 what is the probability of not getting 5 of less?
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Question 237196: A corporate CEO reviews the earnings of three divisions over the last eighteen months. Each division reports its earnings quarterly. Based on the earnings below, is there sufficient evidence to conclude, at the 99% level of confidence, that one of these divisions is more profitable than the others?
Division I
42,1,48,55,56,47
Division II
33,36,40,20,13,19
Division III
21,1,26,8,18,1

· State the null and alternate hypotheses
· Calculate the sums of squares SS(total), SS(factor), and SS(error)
· Calculate the degrees of freedom df(total), df(factor), and df(error)
· Calculate the mean square for factor, and the mean square for error
· Calculate the F-statistic
· Determine the critical value(s)
· State your decision: Should the null hypothesis be rejected?
I thank the tutor who's willing to help me in solving this problem Thanks a bunch..

Click here to see answer by stanbon(57967)

Question 237334: on a typical day how many automobiles should lakeside olds expect to be lined up at opening
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Question 237359: Mr. Obama borrows money at 6% compound monthly . Two years later, he pays off the loan with a single payment of $5000. How much did he borrow?
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Question 237513: Education Attainment in Millions, U.S. Population 25 and over.
Less than 4 years of high school
Male-14
Female-15
Total-29
4 years high school only
Male-25
Female-31
Total-56
Some college(less than 4 years)
Male-20
Female-24
Total-44
4 years college or more
Male-23
Female-22
Total-45
Total male-82
Total female-92
Grand total-174
FIND THE PROBABILITY THAT A RANDOMLY SELECTED AMERICAN, AGED 25 OR OVER
1) has not completed four years or more of college
2) has not completed four years or high school
3) has completed four years of high school only or less than four years of college
4) has completed less than four years of high school or four years of high school only
5) has completed four years of high school only or is a man
6) has completed four years of high school only or is a woman.
I do not know how to answer these questions. This chapter is all on college math probability and crazy probability equations. Could someone please help. Thanks.
Click here to see answer by stanbon(57967)

Question 237427: The diameters of a wooden dowel produced by a new machine are normally distributed with a mean of 0.55 inches and a standard deviation of 0.01 inches. What percent of the dowels will have a diameter less than 0.56?
(5 points)

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Question 237549: A researcher predicts that listening to music while solving math problems will make a particular brain area more active. To test this, a research participant has her brain scanned while listening to music and solving math problems, and the brain area of interest has a percent signal change of 58. From many previous studies with this same math-problems procedure (but not listening to music), it is known that the signal change in this brain area is normally distributed with a mean of 35 and a standard deviation of 10. Using the .01 level, what should the researcher conclude? Solve this problem explicitly using all five steps of hypothesis testing, and illustrate your answer with a sketch showing the comparison distribution, the cutoff (or cutoffs), and the score of the sample on this distribution. Then explain your answer to someone who has never had a course in statistics (but who is familiar with mean, standard deviation, and Z scores).

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Question 237633: 100C2 has a value of 4,950, what is the value of 100C98?
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Question 237653: How many different groups of 35 cars can be formed from 40 cars?

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Question 237658: Indicate the formula for the following conditions. c(n,r)
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Question 237660: Dave stands on a street corner tossing a coin. He decides to toss the coin 10 times, walking 1 block north if heads and 1 block south if tails. Find the probability he ends up 4 blocks south of his original corner?
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Question 237694: From a group of 3 men and 4 women, a delegation of 2 is selected. What is the expected number of men in the delegation???
I answered (which I am not at all sure about)
P(men) = (3)(2) = 6
P(women) = (4)(2) = 8
6/8 = 3/4
Click here to see answer by stanbon(57967)

Question 237708: Given 2 events A and B within the sample space S; P(A/B)=n(A and B)/n(B)
Use this result to find the probability P(spade/king) when a single card is drawn from a standard 52-card deck.

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Question 237881: A box contains 65 balls numbered from 1 to 65. If 10 balls are drawn with replacement, what is the probability that at least two of them have the same number?
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Question 237830: Ten quarters dated 1990-1999 are tossed. What is the probability of the following
a) tails occurring on 1991 quarter only (b) tails on all 10 quarters (c) exactly 4 tails (d) at least 3 tails

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Question 238028: A statistics class contains 10 students. What is the probability that no two students have the same birthday?
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Question 238029: Given eight cards, numbered 1-8, what is the probability that you could select each card in order, without replacing any cards?
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Question 238007: Please help me solve this problem :

the numbers 1,2,...,10 are written on ten cards and placed in a hat. cards are then draw one by one without replacement. find the probabilities of the following events:
A: exactly three even numbers are obtained in the first five draws;
B: exactly five draws are requied to get three even numbers; i.e. there are two even numbers in the first four draws, followed by an even number on the fifth draw;
C: number 7 occurs on the 4th draw;
D: the largest number obtained in the first three draws is 5.

and thank you in advance
Click here to see answer by edjones(7569)

Question 238130: a six sided die is weighed so that the probability of "4" is 4 times as likely as getting any other number. what is the probability of getting a "1" or a "3"?
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Question 238197: A 3-card hand is drawn from a standard deck of 52 playing cards. Find the probability that the hand contains the given cards.
no clubs
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Question 238064: Carlos, Mary, Rick and Yolanda are students in a class of 17. 4 students in the class are to be selected at random to present a report. What is the probability that Carlos, Mary, Rick and Yolanda are selected in that order?
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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, 21286..21330, 21331..21375, 21376..21420, 21421..21465, 21466..21510, 21511..21555