# Questions on Algebra: Probability and statistics answered by real tutors!

Algebra ->  Algebra  -> Probability-and-statistics -> Questions on Algebra: Probability and statistics answered by real tutors!      Log On

 Ad: Algebrator™ solves your algebra problems and provides step-by-step explanations! Ad: Algebra Solved!™: algebra software solves algebra homework problems with step-by-step help!

 Algebra: Probability and statistics Solvers Lessons Answers archive Quiz In Depth

 Question 344439: 65% of the students are under age 24. If 5 of these students are selected, what is the probability they are all 24 or older.. Well the way I am reading it to me means, if they are selecting 5 from the 65% that are UNDER 24 then my answer is none of the students, right? Help :-/ Click here to see answer by stanbon(57224)

 Question 344431: The question is: The area under the standard normal curve that lies to the left of a z-score is always strictly between __ and __. My first answer was going to be -3 to 3, but as I read I got more confused. I know the area to the left is less than one, so I think it would have to be ___ to 1, but if that were the case, I did not know what to put in the second space since it would be infinite. Can you help me? Thank you. Click here to see answer by stanbon(57224)

 Question 344428: Assume that the SD of monthly rent paid by student in a particular town is \$40. A random sample of 100 students was taken to estimate the mean monthly rent paid by the whole student population. a) What is the standard error of sample mean rent? b) What is the probability that the sample mean exceeds the population mean by more than %5. Click here to see answer by stanbon(57224)

 Question 344325: Suppose Lx = 100-x x= 0,1,2,3,,,,,,,,,,,100 Find the expression npx nqx and e50 Click here to see answer by Fombitz(13828)

 Question 344361: A store has light bulbs from two suppliers, 1 and 2. The chance of supplier 1 delivering defective bulbs is 10% whereas supplier 2 has a defective rate of 3%. Suppose 60% of the current supply of light bulbs came from supplier 1. If one of these bulbs is taken from the current supply and observed to be defective, find the probability that it came from supplier 2. Click here to see answer by stanbon(57224)

 Question 344520: 13. For each of the following, (a) state which two populations are being compared, (b) state the research hypothesis, (c) state the null hypothesis, and (d) say whether you should use a one-tailed or two-tailed test and why. i. In an experiment, people are told to solve a problem by focusing on the details. Is the speed of solving the problem different for people who get such instructions compared to the speed for people who are given no special instructions? ii. Based on anthropological reports in which the status of women is scored on a 10-point scale, the mean and standard deviation across many cultures are known. A new culture is found in which there is an unusual family arrangement. The status of women is also rated in this culture. Do cultures with the unusual family arrangement provide higher status to women than cultures in general? iii. Do people who live in big cities develop more stress-related conditions than people in general? Click here to see answer by stanbon(57224)

 Question 344536: There are 3 red marbles in a bag of 12 marbles. A large bag has a total of 26 marbles, including 7 red marbles. Are the chances of choosing a red marble from each bag the same? Click here to see answer by Fombitz(13828)

 Question 344362: Let the function f(x)={cx^2 0 < x < 3 and 0 otherwise 1. Find c. 2. Find the distribution function F(x). 3. Compute F(1 < x < 3). Click here to see answer by Fombitz(13828)

 Question 344357: A committee of 5 is to be selected from a group of 6 men and 9 women. If the selection is made randomly, what is the probability that the committee consist of 3 men and 2 women? Click here to see answer by stanbon(57224)

 Question 344633: Assume that the duration of a normal human pregnancy can be described by a mean of nine months (270 days) and a standard deviation of one-half month (15 days). Most but not all babies will arrive within two standard deviations of the mean. Therefore, a mother would not expect a baby to arrive sooner than _________ days or later than ______________ days. Click here to see answer by stanbon(57224)

 Question 344588: The speed of a passenger train is 14 mph faster than the speed of a freight train. The passenger train travels 270 miles in the same time it takes the freight train to travel 200 miles. Find the speed of each train. Click here to see answer by Fombitz(13828)

 Question 344507: An unbalanced but otherwise standard 6-faced die is rolled. The probability of getting a 1 is four times the probability of getting any other number. Find the probability of getting an even number. So I get that we need to find the probability of getting a 2, 4, OR 6, because they are the even numbers. Normally the prob. would be 1/6 for each and you would add them together.....but I am confused because the prob. of getting a 1 is four times greater...? Please help! Click here to see answer by stanbon(57224)

 Question 344611: The GCF of 2 numbers is 12 and the LCM is 1980. Find the best pair of numbers that fit this description Click here to see answer by stanbon(57224)

 Question 344603: A retailer sells only 2 styles of stereos, and experience shows that these are in equal demand. 4 customers in sucession come into the store to order stereos. The retailer is interested in their preferences. a) List the possibilites for preference arrangements among the 4 customes b)assign proabablities to the sample points c) Let A denote the event that all 4 customers prefer the same style. Find P(A) Click here to see answer by stanbon(57224)

 Question 344705: Number of siblings per student in a preschool class Number of siblings 0 1 2 3 Number of students 3 6 2 1 The table above shows how many students in a class of 12 preschoolers had 0, 1, 2, or 3 siblings.Later, a new student joined the class, and the average (arithmetic mean) number of siblings per student became equal to the median number of siblings per student. How many siblings did the new student have? A. 0 B. 1 C. 2 D. 3 E. 4 Click here to see answer by edjones(7569)

 Question 344352: How many different signals, each consisting of 9 flags hung in a line, can be made from a set of 4 white flags, 3 red flags, and 2 blue flags if all flags of the same color are identical? Click here to see answer by stanbon(57224)

 Question 344773: Assume your alarm clock has a 0.195% probability of working on every given morning. What is the probability that your alarm clock will not work on the morning of a important final exam? Click here to see answer by Alan3354(30968)

 Question 344771: 8 couples try to have baby girls, what is the probability that all 8 couples will be girls? I can't figure out how to do this can you please show me? Click here to see answer by stanbon(57224)

 Question 344856: A 7-card hand is chosen from a standard 52-card deck. How many of these will have five spades and two hearts? Click here to see answer by stanbon(57224)

 Question 344855: Serial numbers for a product are to be made using four letters (using any letter of the alphabet) followed by three single-digit numbers. For example, JDGR209 is one such serial number. How many such serial numbers are possible if neither letters nor numbers can be repeated? Click here to see answer by checkley77(12569)

 Question 344857: There are 12 students fro whom 5 are going to be chosen to represent their school at a conference. If Jack, Anna, or Chris, but only one of them, must be chosen, in how many ways can the students be chosen to go to the conference? Click here to see answer by stanbon(57224)

 Question 344874: Four engineers A,B,C and D have been scheduled for job interviews. The personnel manager has scheduled the four for interview rooms 1,2,3,and 4 respectively. However the manager's secretary does not know this, so assigns them to the four rooms in a completely random fashion. What is the probability that A. All four end up in the correct rooms? B. None of the four end up in the correct room? Click here to see answer by stanbon(57224)

 Question 344868: Suppose that the weight of apples eaten by individual Americans can be described by a normal probability distribution with mean u=15 pounds and standard deviation o= 5 pounds per 1. for a random sample of n= 16 people, what is the standard deviation of the sampling distribution of the sample mean x? 2. for a random sample of n=16 people, what is the mean of the sampling distribution of the sample mean x? 3. for a random sample of n=16 people, what is the z-score for a sample means x=10 pounds? 4. for a random sample of n=9 people, what is the z-score for a sample means x=18 pounds Click here to see answer by stanbon(57224)

 Question 344945: Please solve this question for me. Thank you! A student is taking two courses, history and math. The probability the student will pass the history course is .60, and the probability of passing the math course is .70. The Probability of passing both is .50. What is the probability of passing at least one? Click here to see answer by user_dude2008(1861)

 Question 344986: What is the number of distinguishable arrangements that can be made from the word KITCHEN, if the vowels must stay together? Click here to see answer by Edwin McCravy(8880)

 Question 344944: Please answer this question. I am having difficulty understanding this course my Professor does not speak English well, and has problems explaining the steps to the class. Thank you The following frequency distribution reports the electricity cost for a sample of 50 two-bedroom apartments in Albuquerque, New Mexico during the month of May last year. Electricity Cost Frequency \$80 up to \$100 3 100 up to 20 8 120 up to 140 12 140 up to 160 16 160 up to 180 7 180 up to 200 4 - Total 50 a. Estimate the mean cost. b. Estimate the standard deviation. c. Use the Empirical Rule to estimate the proportion of costs within two standard deviations of the mean. Waht are these limits? Click here to see answer by stanbon(57224)

 Question 345025: A sample of 65 observations is selected from one population with a population standard deviation of 0.75. The sample mean is 2.67. A sample of 50 observations is selected from a second population with a population standard deviation of 0.66. The sample mean is 2.59. Conduct the following test of hypothesis using the .08 significance level. H0: u1 < u2 H1: u1 >u2 a. Is this a one-tailed or a two-tailed test? b. State the decision rule. c. Compute the value of the test statistic. d. What is your decision regarding H0? e. What is the p-value? Click here to see answer by stanbon(57224)

 Question 345162: Please help. Following are the speeds of 40 cars clocked by radar on a particular road in a 35-mph zone on a particular afternoon: 30, 36, 42, 36, 30, 52, 36, 34, 36, 33, 30, 32, 35, 32, 37, 34, 36, 31, 35, 20, 24, 46, 23, 31, 32, 45, 34, 37, 28, 40, 34, 38, 40, 52, 31, 33, 15, 27, 36, 40 A) make a frequency table B) a histogram c) describe the general shape of the distribution Any help with this problem would be appreciated Click here to see answer by Edwin McCravy(8880)
 Question 345162: Please help. Following are the speeds of 40 cars clocked by radar on a particular road in a 35-mph zone on a particular afternoon: 30, 36, 42, 36, 30, 52, 36, 34, 36, 33, 30, 32, 35, 32, 37, 34, 36, 31, 35, 20, 24, 46, 23, 31, 32, 45, 34, 37, 28, 40, 34, 38, 40, 52, 31, 33, 15, 27, 36, 40 A) make a frequency table B) a histogram c) describe the general shape of the distribution Any help with this problem would be appreciated Click here to see answer by jim_thompson5910(28476)

 Question 345271: Two students are selected at random from a class of 13 males and 7 females. Find the probability that both students are males. (See Example 4. Round your answer to two decimal places.) Click here to see answer by stanbon(57224)
 Question 345271: Two students are selected at random from a class of 13 males and 7 females. Find the probability that both students are males. (See Example 4. Round your answer to two decimal places.) Click here to see answer by checkley77(12569)

 Question 345251: 1. high school dropouts. Approximately 10% of american high school students drop out of school before graduation. choose 15 students entering high school at randon. Find the probability that only 10 students will graduate. Click here to see answer by stanbon(57224)

 Question 345298: For a random sample of 12 observations, the sample mean was 407 and the sample standard deviation 6. Using the .01 significance level: a. State the decision rule. b. Compute the value of the test statistic. c. What is your decision regarding the null hypothesis? Click here to see answer by stanbon(57224)

 Question 345231: A student scores 62 on a geography test and 246 on a mathematics test. The geography test has a mean of 80 and a standard deviation of 15. The mathematics test has a mean of 300 and a standard deviation of 36. If the data for both tests are normally distributed, on which test did the student score better relative to the other students in each class? Click here to see answer by stanbon(57224)

 Question 345351: heavy drinking and smoking have been demonstrated to be great risk factors for throat cancer. Research has demonstrated an OR (odds ratio) of 38:1. What does this mean? Is it that they are 38 times more likely to get it? and if so, 38 more times more likely to get it over and above what???? Click here to see answer by rfer(12646)

 Question 345380: This question deals with a 52 card deck. There are 2 cards of one denomination and 1 card of another denomination. How do you solve this using combination method? Click here to see answer by stanbon(57224)

 Question 345326: An experiment consists of tossing a penny, a nickel, a dime, and a quarter. Write the probability distribubtion. Click here to see answer by stanbon(57224)

 Question 345439: The Transportation Safety Authority (TSA) has developed a new test to detect large amounts of liquid in luggage bags. Based on many test runs, the TSA determines that if a bag does contain large amounts of liquid, there is a probability of 0.92 the test will detect it. If a bag does not contain large amounts of liquid, there is a 0.1 probability the test will conclude that it does (a false positive). Suppose that in reality only 3 in 100 bags actually contain large amounts of liquid. A)What is the probability a randomly selected bag will have a positive test? Give your answer to four decimal places. Click here to see answer by haileytucki(390)

 Question 345445: A jar holds two color of marbles. The jar is composed of 60% black marbles and 40% red marbles. You select 6 marbles. What is the probability that you selected AT LEAST one of each color? Click here to see answer by stanbon(57224)

 Question 345425: Component 1 has an exponential failure rate of 2X10exp-2 failures per hour. component 2 is normally distributed with a mean of 200 hours and standard deviation of 50 hurs. Assuming independence, calculate the reliability of the system after 50 hours. ------Component 1----------component 2--------------- Click here to see answer by stanbon(57224)

 Question 345319: A normal distribution has a mean of 80 and a standard deviation of 14. Determine the value above which 80 percent of the values will occur. Click here to see answer by stanbon(57224)

 Question 345412: 1. For this lab assignment, the experiment is to roll a fair die twice. If the random variable x represents the sum of the numbers rolled, find the probability distribution for this random variable. Click here to see answer by stanbon(57224)

 Question 345173: In a deck of cards, five are pulled at random. What is the probabilty that exactly three of them will be spades? Click here to see answer by stanbon(57224)

 Question 345089: 1. For this lab assignment, the experiment is to roll a fair die twice. If the random variable x represents the sum of the numbers rolled, find the probability distribution for this random variable. This should be in the form of a table similar to Table 5-1 on Page 195 in the textbook. Click here to see answer by stanbon(57224)

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