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

Tutors Answer Your Questions about Probability-and-statistics (FREE)

Question 292242: There are 15 balls in a rectangular box 5 are red, 6 are yellow and the rest is green. If 2 balls are selected at random without replacement one after the other, what is the probability that they are: a) both green (b) of the same color.
Click here to see answer by Alan3354(30993)

Question 292344: two six-sided dice are rolled. find the probability of the given event. 35. the sum is not three.
Click here to see answer by stanbon(57290)

Question 292341: what is the 70th percetile of these numbers 25, 28, 32, 39, 41, 42, 47, 51, 54, 55, 66, 68, 69, 70, 71, 72, 74, 76, 77, 79, 80, 82
Click here to see answer by stanbon(57290)

Question 292320: Of 30 people who went fishing in Lake Mead, 22 were fishing for bass. Find the emperical probabilty that the next person who goes fishing in lake mead will be fishing for bass.
Click here to see answer by stanbon(57290)

Question 292317: 1. Find the Critical t value that corresponds to 96 % confidence. Assuming 6 degrees of freedom.
2. Constuct a 99% confidence interval for the proportion of adults aged 18 or older who believe there is to little spending on national defense.

Click here to see answer by stanbon(57290)

Question 292408: Could you show me how to do this problem?
-Design and conduct a simulation to determine the ages of 20 licensed drivers chosen ar random in the United States.

And then the table that came with it looks like this:
Licensed drives in the United States, by Age
a-<20, 20-29, 30-39, 40-49, 50-50, 60-60, 70-79, >/_80
P(a)-0.051, 0.176, 0.211, 0.211, 0.156, 0.096, 0.070, 0.029

Click here to see answer by stanbon(57290)

Question 292641: Three quarters, two dimes, and five nickels are placed in a bag. A coin is randomly chosen and not replaced. Another coin is chosen. What is the probability that both are quarters? how do you get the answer to this?

Click here to see answer by scott8148(6628)

Question 292753: can a student realistically have a Z-score of -6?
Click here to see answer by stanbon(57290)

Question 292765: Please help me solve this problem:
Oftentimes, a new deck of cards will include two jokers. If selecting three cards from this brand new deck, what is the probability that you will pick a spade followed by the Queen of spades followed by a Joker?
Click here to see answer by richwmiller(9135)

Question 292711: What is the probability? You are given a multiple choice test consisting of 10 questions. Each question has 4 choices. If you guess at all of the answers, what is the probability that you will choose the incorrect answer for each question?

Click here to see answer by dabanfield(803)

Question 292284: AAA reports that of the fatal car and truck accidents, 54% are cause by car driver error. If 3 accidents are chosen at random, find the probability that all are caused by car driver error.
Click here to see answer by stanbon(57290)

Question 292204: If a student randomly guesses on each of 25 questions he has a 1 out of 5 (20%) chance of getting a correct answer since it is a multiple choice exam with choices a,b,c,d,and e. What is the probability that the student will get 16 or more correct? What is the probability the student will get 15 or less correct?
I know that n=25 and p=.2 I tried binomial probability and computation, neither worked right. What do you suggest?
Click here to see answer by stanbon(57290)

Question 293084: 84°13'- 27°45'
Click here to see answer by richwmiller(9135)

Question 293084: 84°13'- 27°45'
Click here to see answer by Alan3354(30993)

Question 293131: The length of the hypotenuse of a right triangle equals the length of one of the legs of the triangle.
a.) Always true
b.) Sometimes true
c.) Never true

Click here to see answer by stanbon(57290)

Question 293129: The length of the hypotenuse of a right triangle equals the length of one of the legs of the triangle.
a.) Always true
b.) Sometimes true
c.) Never true

Click here to see answer by stanbon(57290)

Question 293128: A state weights-and-measures standard requires that no more than 5 percent of bags of Halloween candy be underweight.A random sample of 200 bags showed that 16 were underweight. (a) At α = .025, is the standard being violated? Use a right-tailed test and showyourwork. (b) Find the p-value.
Click here to see answer by stanbon(57290)

Question 293135: Experience shows that a ski lodge will be full (156 guest) if there is a heavy snow fall in December, while only partially full (57 guest) with a light snow fall. What is the expected number of quest if the probability for a heavy snow fall is .40?
a.96.6
b.93.6
c.116.4
d.62.4

Click here to see answer by stanbon(57290)

Question 293125: Hi, can anyone help me here. Can you show me the steps. Thanks in advance
A sample of 40 CDs from a student’s collection showed a mean length of 52.74 minutes with a standard deviation of 13.21 minutes. Construct a 95 percent confidence interval for the population standard deviation.
Click here to see answer by stanbon(57290)

Question 293096: if a student randomly guesses at 20 multiple choice questions find the probability that the student gets exactly 5 correct? each question has 4 possible choices.
B. student gets at MOST 5 correct?
C. student gets MORE than 7 correct?
D. Student gets at LEAST 8 correct?
Click here to see answer by stanbon(57290)

Question 293205: A game is played by flipping three coins. If all three coins lands heads up you win $15. If two coins lands heads up you win $5. If one coin lands heads up you win $2. If no coin land heads up you win nothing. If you play $4 to play, what are your expected winnings?
answer choice
a. $1.00
b. -$1.00
c. -$0.50
d. $0.50
Click here to see answer by stanbon(57290)

Question 293230: If two people are selected at random, find the probability that they have the same birthday (both month and day).
Click here to see answer by Alan3354(30993)

Question 293233: Probability of getting at least 65 girls in 100 births
Click here to see answer by Edwin McCravy(8904)

Question 293251: 9.22 The mean arrival rate of flights at O’Hare Airport in marginal weather is 195 flights per hour with a historical standard deviation of 13 flights. To increase arrivals, a new air traffic control procedure is implemented. In the next 30 days of marginal weather the mean arrival rate is 200 flights per hour. (a) Set up a right-tailed decision rule at a =.025 to decide whether there has been a significant increase in the mean number of arrivals per hour. (b) Carry out the test and make the decision. Is it close? Would the decision be different if you used a = .01? (c) What assumptions are you making,
if any? Flights
210 215 200 189 200 213 202 181 197 199
193 209 215 192 179 196 225 199 196 210
199 188 174 176 202 195 195 208 222 221

Click here to see answer by stanbon(57290)

Question 293293: A fair coin is tossed until first tail comes up. Let A be the event that the number of tosses is divisible by 5, b be the event that the number of tosses is less than 6
Find P(A) P(B) P(AuB)
Can someone please talk me through the method to solve these
Thank You
Click here to see answer by stanbon(57290)

Question 293362: The weights of lemons in a large crate have a distribution with μ = 136 grams and σ = 4.1 grams. Consider the random process of picking three lemons independently and putting them in a bag. The standard deviation of the total weight of the three lemons in the bag is? What would be the best way to work this out?

Click here to see answer by stanbon(57290)

Question 293222: Suppose that the heights of adult women in the United States are normally distributed with a mean of 64.5 inches and a standard deviation of 2.4 inches. Jennifer is taller than 70% of the population of U.S. women. How tall (in inches) is Jennifer? Carry your intermediate computations to at least four decimal places. Round your answer to at least one decimal place.
I can work it out to the point where P(Z>(x-64.5/2.4)=0.7
I don't really get the explanation that I have in front of me so I tried a websearch. I found a lot of answers to similar problems, but most of the answers require graphing calculators and I'm working by hand. I would appreciate some advice on what to do next.
Click here to see answer by stanbon(57290)

Question 293416: If the correlation coefficient is 0.145, what is the sign of the slope of th regression line?
As the correlation coefficient decreases from 0.84 to 0.79, do the points of the scatter plot move toward the regression line, or away from it?
Click here to see answer by stanbon(57290)

Question 293415: In terms of the mean and standard deviation:
What does it mean to say that a particular value of x has a standard score of +1.17.
What does it mean to say that a particular value of x has a z-score of -5.9?
Click here to see answer by stanbon(57290)

Question 293441: how many different ways can a researcher select three mice from 15 mice and assign them each to a different test?
thank you!
Click here to see answer by unlockmath(1599)

Question 293450: a box contains a penny, a nickel, a dime, and a quarter. A coin is drawn at random and not replaced. a second coin is drawn. How many out comes are possible?
thank you!
Click here to see answer by richwmiller(9135)

Question 293487: suppose a fair coin is tossed 7 times. What is the probability of flipping exactly 2 heads?
Click here to see answer by Edwin McCravy(8904)

Question 293650: There are 12 balloons in a bag: 3 each of blue, green, red, and yellow. Three balloons
are chosen at random. Find the probability that all 3 of the balloons are green.
Click here to see answer by brucewill(101)

Question 293588: Suppose the probability of selling a car today is 0.34. what are the odds of selling a car today?
Click here to see answer by brucewill(101)

Question 293661: The coach randomly selects 3 swimmers from a team of 8 to swim in a
heat. What is the probability that she will choose the three strongest swimmers?
Click here to see answer by stanbon(57290)

Question 293565: A random sample of 10 miniature Tootsie Rolls was taken from a bag. Each piece was weighed on
a very accurate scale. The results in grams were
3.087 3.131 3.241 3.241 3.270 3.353 3.400 3.411 3.437 3.477
(a) Construct a 90 percent confidence interval for the true mean weight. (b) What sample size
would be necessary to estimate the true weight with an error of ± 0.03 grams with 90 percent confidence?
(c) Discuss the factors which might cause variation in the weight of Tootsie Rolls during
manufacture. (Data are from a project by MBA student Henry Scussel.)
Click here to see answer by stanbon(57290)

Question 293668: There are 7 books numbered 1–7 on the summer reading list. Peter randomly
chooses 2 books. What is the probability that Peter chooses books numbered 1 and 2?
Click here to see answer by stanbon(57290)

Question 293548: license plates in a particular state display 2 letters followed by 2 numbers. how many different license plates can be manufactured? (repetitions are allowed)
Click here to see answer by stanbon(57290)

Question 293699: 10.3 In 1999, a sample of 200 in-store shoppers showed that 42 paid by debit card. In 2004, a sample
of the same size showed that 62 paid by debit card. (a) Formulate appropriate hypotheses to test
whether the percentage of debit card shoppers increased. (b) Carry out the test at α = .01. (c) Find
the p-value. (d) Test whether normality may be assumed.

Click here to see answer by stanbon(57290)

Question 293874: If 3 dice are rolled at the same time, what is the probability of all 3 dice showing even face
values? (i.e. all 3 dice showing 2, 4, or 6)

If 2 dice are rolled at the same time, what is the probability of the 2 dice having the same face
value?
Click here to see answer by Edwin McCravy(8904)

Question 293891: A state lottery requires you to pick 6 different numbers from 1 to 40 to win $1,000,000. A) what is the probability of winning if order is not important?
B) If you pick 5 of the 6 numbers correctly you win $10,000. What is the probabilty of winning?
Click here to see answer by Edwin McCravy(8904)

Question 293926: a jar contains 100 marbles. there are 7 blue marbles, 4 green marbles, 46 red marbles, and 43 yellow marbles. what is the probability of randomly selecting a yellow marble?
Click here to see answer by edjones(7569)

Question 293915: The “Cash 5” game in the Virginia Lottery requires that you select 5 different numbers from 34 in order to play the game. If you buy one ticket, what is the probability that you will win? Hints: Order IS NOT important here. First find the # of combinations and then calculate the probability.
Click here to see answer by edjones(7569)

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