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Question 619294: suppose you receive a shipment of 30 computers, 2 of which are defective. What is the probability of picking a sample of 5 computers with 2 defective computers in it?
Click here to see answer by Theo(3472)

Question 619302: Can anyone help me with this? I need to show my work but not sure what steps I need to take to solve this.
X has a normal distribution with a mean of 80.0 and a standard deviation of 3.5. Find the following probabilities:
(A) P(x < 77.0)
(B) P(75.0 < x < 85.0)
(C) P(x > 85.0)
Click here to see answer by stanbon(57424)

Question 619337: Dear tutor, please help me..how many probability for word COMBINE to :
- start with C and end with E?
- start with C or end with E?
- with I and N separated?
- with alternating vowels and consonants?
-if a 5 letter word instead of 7 letter word is made from COMBINE, how many probability are that has exactly 3 consonants?
greatly appreciate. thank you
Click here to see answer by stanbon(57424)

Question 619248: There are 7 juniors and 11 seinors on a swim team. Out of these swimmers, 4 co-captains will be chosen. How many ways can these swimmers be chosen if there are 2 spots for juniors and 2 spots for seinors.
Click here to see answer by ewatrrr(10682)

Question 619395: Assume the random variable x is normally distributed with mean 81 and standard deviation 5. Find the indicated probablilty. P(68
Click here to see answer by stanbon(57424)

Question 619410: There were seven students running in a race.how many different arrangements of 1st 2nd and 3rd place are possible.
Click here to see answer by ewatrrr(10682)

Question 619411: A bag of marbles contains 2green one blue and 3red. If 2 marbles are selected at random without replacement what is the probablilty that both will be green
Click here to see answer by ewatrrr(10682)

Question 619563: In a city the probability that a person will pass his or her driving test the first attempt is 0.66. Four people are selected at Random from among those taking their driving test for the first time. Determine the following:
a. The probability that exactly one person passed
b. The probability that at least two persons passed the test
Click here to see answer by stanbon(57424)

Question 619565: An economics class is comprised of 3 female and 10 male students. If the instructor of the class randomly chooses 9 students from the class for an oral exam, what is the probability that 2 female students and 7 male students will be selected? Round your answer to decimal places.
Please help. I just can't get this one.

Click here to see answer by math33(31)

Question 619596: A warehouse employs 24 workers on the first shift and 17 on the second shift. Eigth workers are chosen at random to be interviewed. Find the probability of choosing 4 out the second shiff
Click here to see answer by stanbon(57424)

Question 619626: How many 7 digit phone numbers are possible if order matters?
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Question 619639: what is the probability that a student will answer at least nine questions correctly by random guessing on an exam with 10 multiple choice questions each of which has four options?
Click here to see answer by stanbon(57424)

Question 619614: 1/4(x+4)=9
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Question 619802: I need some help with this question please.
I would appreciate some hints. Thank you.
You are applying for a job at two companies. Company A offers salaries with μ = $53,000 and σ = $4,000 and company B offers salaries with μ = $53,000 and σ = $2, 000. Which company is most likely to offer a starting salary more than $58, 000?
Click here to see answer by vleith(2825)

Question 619778: three tickets selected at random from 100 ticket bearing number from 1 to 100. calculate the probablity that the maximum number on the ticket drawn is greater than 50

Click here to see answer by richard1234(5390)

Question 619872: A ceramic jar contains 48 quarters and 21 dimes. If two coins are randomly drawn in succession without replacement what is the probability that the total value of the coins is .20? I have taken 21/69 x 20/68 amd come up with the answer of 5/391 but this is not one of the options. The answers given to me on the study sheet are 188/391 147/1564 35/391 or 84/391. I am not sure what I have done wrong if anything and how this number is achieved. Help please
Click here to see answer by stanbon(57424)

Question 619850: A box contains 25% black balls and 75% white balls. The same number of black balls as were in the box are added (so new number of black balls is twice the original number). A ball is now drawn from the box at random. What is the probability that it is black?
Click here to see answer by stanbon(57424)

Question 619788: Mobile homes are tightly constructed for energy conservation. This can lead to a buildup of indoor pollutants. The paper "A Survey of Nitrogen Dioxide Levels Inside Mobile Homes" discussed various aspects of NO2 concentration in these structures.
(a) In one sample of mobile homes in the Los Angeles area, the mean NO2 concentration in kitchens during the summer was 36.66 ppb, and the standard deviation was 11.44. Making no assumptions about the shape of the NO2 distribution, what can be said about the percentage of observations between 13.78 and 59.54? (Round the answer to the nearest whole number.
(b) Inside what interval is it guaranteed that at least 89% of the concentration observations will lie?

Click here to see answer by stanbon(57424)

Question 619722: Sarah has a deck of 52 cards and ramdomly selects 2. What is the probability that she will pick the same cards?
Click here to see answer by stanbon(57424)

Question 619946: Hi, I was wondering if I could get some help understanding how to do this question:

How long do new batteries last on a camping trip? n1 = 42 random small camp flashlights
were fitted with brand 1 batteries and left on until the batteries failed. The sample mean
lifetime was x = 9.8 hours. Another n2 = 38 random small flashlights of the same model
were fitted with brand II batteries and left on until the batteries failed. The sample mean for
lifetimes was x = 8.1 hours. Historical data suggests that σ1 = 2.2 hours and σ2 = 3.5 hours. Find a 90% confidence interval for the population difference of lifetimes for
these batteries.
Click here to see answer by stanbon(57424)

Question 620094: if a single 9-sided die is tossed once, find the probability of rolling a number less than 2
Click here to see answer by Edwin McCravy(8921)

Question 620146: My price is $64,413.02, which is 45.9% higher than my competitor's price. What is my competitor's price?
Click here to see answer by fcabanski(874)

Question 620205: Determine whether each of the distributions given below represents a probability distribution. Justify your answer.
(A)
x 1 2 3 4
P(x) 0.01 7/12 1/12 1/4
(B)
x 3 6 8
P(x) 0.24 3/5 0.135
Click here to see answer by solver91311(16897)

Question 620125: Assume that a procedure yields a binomial distribution with a trial repeated n times. Use the Binomial Probability Formula to find the probability of x successes given the probability p of successes on a single trial n=6, x=4, p=0.55, q=0.45
Click here to see answer by math-vortex(472)

Question 620235: Nine college students had eaten the following number of times at a fast food restaurant for dinner in the last ten days:

5, 2, 4, 0, 4, 6, 4, 2, 3

Find the mean, median, mode, range, and midrange for these data. Please show all of your work.

Click here to see answer by solver91311(16897)

Question 620234: Please show all of your work when answering the following:

I. Use Chebyshev’s theorem to find what percent of the values will fall between 248 and 320 for a data set with a mean of 284 and standard deviation of 18.

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 216 and standard deviation of 15.

Click here to see answer by ewatrrr(10682)

Question 620237: Starting with the data values 70 and 100, add three data values to the sample so that the mean is 86, the median is 82, and the mode is 82. Please show all of your work.

Click here to see answer by ewatrrr(10682)

Question 620240: a highly selective boarding school will only admit students who place at least 2 standard deviations above the mean on a standardized test that has a mean of 300 and a standard deviation of 24. What is the minimum score that an applicant must make on the test to be accepted?
Click here to see answer by ewatrrr(10682)

Question 620256: kamal get 6 out of every 8 questions on a test correct .If he get 27 questions correct how many questions are on the test
Click here to see answer by ewatrrr(10682)

Question 620277: the age group normally dostribute with a men of 52 years in a standard divotion of 6 years . one women is randomly selected from the group and her age is observed. find the probability that her age will fall between 55 and 60 years

Click here to see answer by richard1234(5390)

Question 619963: Hi, I've been stuck on this question all day! Hoping I could get some help:
Whats the height of college hockey players? The avg height has been 68.3 inches. A random
sample of 14 hockey players gave a mean height of 69.1 inches. We may assume that x has a normal distribution with std dev of 0.9 inch. Does this indicate that the population mean height is
different from 68.3 inches? Use 5% level of significance
and this one as well please:
A random sample of 83 investment portfolios managed by Kendra showed that 62 of them met the targeted annual percent growth. A random sample of 112 portfolios managed by Lisa showed that 87 met the targeted annual percent growth. Find a 99% confidence interval for the difference in the proportion of the portfolios meeting target goals managed by Kendra compared with those managed by Lisa. Is there a difference in the proportions at the 99% confidence level?
Click here to see answer by stanbon(57424)

Question 620301: what is the 6th term of (2x-1/3y)^7
Click here to see answer by stanbon(57424)

Question 620338: 24 teams enter the basketball tournament. How many different arrangements for 1st 2nd and 3rd place are there?
Click here to see answer by nerdybill(6963)

Question 620444: 1 3 5 7 9 11 13 15 17 19=100 , To Make 50 Use Only 5 Digits ...? What The 5 Digits
Click here to see answer by lynnlo(4164)

Question 620534: 14% of what number is 0.3
Click here to see answer by stanbon(57424)

Question 620528: If the period of a tangent function is 7π, what is the frequency of the function?
Click here to see answer by stanbon(57424)

Question 620509: Solve Probability Problems. P(x>450) Mean=390 Deviation=65
Click here to see answer by stanbon(57424)

Question 620632: If a population has a standard deviation of 18, what is the minimum number of samples that need to be averaged in order to be 95% confident that the average of the means is within 2 of the true mean?
Click here to see answer by stanbon(57424)

Question 620635: A medication is 75% effective against a bacterial infection. Find the probability that if 12 people take the medication, at least 1 person's infection will not improve
Click here to see answer by stanbon(57424)

Question 620582: Hello, may you please help me solve:
Is it more profitable to receive $1000 now or $1700 in nine years? Assume that money can earn 6% interest compounded annually.
Thank you!
Click here to see answer by nerdybill(6963)

Question 620705: if 1+3+5+7+9+11+13+15+17+19=100 then please tell me from these 1 to 19 odd numbers whose 5 numbers sum is 50.
Click here to see answer by math-vortex(472)

Question 620707: Solve: 73x is congruent to(the three line equal symbol) 115 (mod 971).
I know you can change this to (73x-115)/971, but I'm not sure how to solve the rest of this.
Click here to see answer by jim_thompson5910(28598)

Question 620821: an urn contains 4 green, 5 blue, 2 red and 3 yellow marbles
so if eight marbles are drawn random, what is the probability that there are equal number of marbles of each colour?
Click here to see answer by ewatrrr(10682)

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