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

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

Question 468803: Question 1: In a large population, 63 % of the people have been vaccinated. If 4 people are randomly selected, what is the probability that AT LEAST ONE of them has been vaccinated?

Click here to see answer by ccs2011(207)

Question 468888: i really need some help with this problem, I am really struggling with it.

Information from the American Institute of Insurance indicates the mean amount of life
insurance per household in the United States is $110,000. This distribution follows the
normal distribution with a standard deviation of $40,000.
a. If we select a random sample of 50 households, what is the standard error of the mean?
b. What is the expected shape of the distribution of the sample mean?
c. What is the likelihood of selecting a sample with a mean of at least $112,000?
d. What is the likelihood of selecting a sample with a mean of more than $100,000?
e. Find the likelihood of selecting a sample with a mean of more than $100,000 but less
than $112,000.
Click here to see answer by stanbon(57409)

Question 468932: Two dice are rolled simultaneously. Find the probability of a roll of a two and a three (order does not matter).
Click here to see answer by jorel1380(2518)

Question 468938: You plan to conduct a survey to find what proportion of the workforce has two or more jobs. You decide on the 95 percent confidence level and state that the estimated proportion must be within 2 percent of the population proportion. A pilot survey reveals that 5 of the 50 sampled hold two or more jobs. How many in the workforce should be interviewed to meet your requirements?

Click here to see answer by stanbon(57409)

Question 468923: Assume that the population of heights of female college students is approximately normally distributed with mean m of 64 inches and standard deviation s of 4.00 inches. Show all work.
(A) Find the proportion of female college students whose height is greater than 62 inches.
(B) Find the proportion of female college students whose height is no more than 62 inches.

Click here to see answer by stanbon(57409)

Question 468869: A particular sample contains 50 data values. According to Chebyshev's theorem, which of the following is the number of values you would expect to fall within 3.0 standard deviations of the mean? A. 5, B. 25, C. 35, D. 45. Can you please show the steps to achieving this answer?
Click here to see answer by kingme18(98)

Question 468990: a rotary club is holding a charity fundraise to bolster its college scholarship fund. The club is selling 2000 raffle tickets for $10 each. to keep the problem simple, assume a ticket can win more than on prize. the prizes are as follows
1-first prize valued at $5000
4-second prizes valued at $500
10-third prizes valed at $100
compute the expected vlue for a player purchsing a single ticket
Click here to see answer by stanbon(57409)

Question 468988: Lucky downs runs n exact each evening. To win, a better must select the first two horses in order. Seven horses compete in each race. Im being told to use one of the counting rules to determine the number of winning pairs of numbers that can occur and to show formula and work...IM STUMPED..
Click here to see answer by stanbon(57409)

Question 468918: What probability rule is this and how to I solve it?
From a group of 9 people, you randomly select 4 of them.
What is the probability that they are the 4 oldest people in the group?
Give your answer as a fraction.
Click here to see answer by stanbon(57409)

Question 468874: The letters of the word mathematics are written on separate pieces of paper and put in a hat. What are the odds against drawing a vowel from the hat? (vowels are a, e, i, o, u)
Click here to see answer by stanbon(57409)

Question 468994: Essay; show all work. A simple dartboard has three areas… the main board has a radius of 9 inches, there is a circle with a radius of 5 inches, and the bullseye has a radius of 3 inches. What is the probability of a random dart landing inside the bullseye?

Round to the nearest thousandth. (Hint: Use A=
Click here to see answer by jorel1380(2518)

Question 468872: If 8 teams are drawn from a hat what are the odds of the same teams being drawn in the same order a second time?
Click here to see answer by stanbon(57409)

Question 468770: One card is selected from a deck of cards. Find the probability of selecting a red card or a card less than 10 . (Note: The ace is considered a low card.)

A. 47/52
B. 23/26
C. 21/26
D. 11/13

I know that there are 52 cards total and 20 red cards. I do not know my next step in solving. Plese Help me.
Click here to see answer by stanbon(57409)

Question 469011: Can a tutor so kindly review these problems and show me how to do them step by step?
Suppose the scores of certain standardized test are normally distributed with mean 500 and standard
deviation 60.
8. (1 point) What percent of the test takers have a score of 440 or less? Round answer to four places after
the decimal point.
9. (1 point) What percent of the test takers have a score of 590 or more? Round answer to four places
after the decimal point.
10. (1 point) What percent of the test takers have a score between 440 and 590? Round answer to four
places after the decimal point.
11. (1 point) Suppose a college will only admit students who score in the top 20% among all test takers,
what will be the minimum required score be? Round answer to the nearest whole number.
Click here to see answer by stanbon(57409)

Question 469028: I am so stuck on this problem. Please help. This is a deck of 20 cards.
You have 4 rows of cards and they are numbered from 1-5 as follow.
First row - 1, 2, 3, 4, 5
Second row - 1, 2, 3, 4, 5
third row - 1, 2, 3, 4, 5
forth row - 1, 2, 3, 4, 5
Two cards are selected at random from this deck. Determine the probability of both cards being even numbers.
Click here to see answer by stanbon(57409)

Question 469022: If Z-score=(7-5)/1=2 and at .05 significance level for a one-tailed test, the z-score cut-off value = +1.645
"Can you show me how you got the answer +1.645 for the cut off value?"

Click here to see answer by stanbon(57409)

Question 469045: find the probability of obtaining exactly two 5's in six rolls of a fair die.
Click here to see answer by jorel1380(2518)

Question 469024: I need a tutor to review these and tell me if I am performing the operations correctly. I am not sure if I am going about it right...
Suppose the scores of certain standardized test are normally distributed with mean 500 and standard
deviation 60.
8. (1 point) What percent of the test takers have a score of 440 or less? Round answer to four places after
the decimal point.
500-440= 60/60 = 1
1= .8413
9. (1 point) What percent of the test takers have a score of 590 or more? Round answer to four places
after the decimal point.
590-500= 90/60= 1.5
1.5= .9332
10. (1 point) What percent of the test takers have a score between 440 and 590? Round answer to four
places after the decimal point.
.9332-.8413= 1.5 - 1 = .6915
11. (1 point) Suppose a college will only admit students who score in the top 20% among all test takers,
what will be the minimum required score be? Round answer to the nearest whole number.
.20= .8416 = x-500= 80.496= 580
Click here to see answer by ccs2011(207)

Question 469027: I would be truly grateful if a tutor could show me how to do these prblems or at least give me the equation to set them up.
With probability 0.05 a robotic reporter that works for MEOW NEWS will make a false statement.
Suppose the reporter produced 1900 statements last week.
12. (1 point) What is the expected number of false statements, and the standard deviation?
13. (1 point) What is the probability that 85 or fewer of those statements were false? Round answer to
four places after the decimal point.
14. (1 point) What is the probability that 124 or more of those statements were false? Round answer to
four places after the decimal point.
-------------------------------------------------------------------
Click here to see answer by stanbon(57409)

Question 469114: According to insurance records a car with a certain protection system will be recovered 92% of the time. Find the probability that 3 of 7 stolen cars will be recovered
Click here to see answer by stanbon(57409)

Question 469090: A state legislature has a budget committee that consists of 12 democrats and 10 republicans. They decide to form an 8 person subcommitee on taxation and revenue. What is the probability that the subcommittee consists of 4 democrats and 4 republicans?
Click here to see answer by stanbon(57409)

Question 469141: What is the slope of a binomial 2x+3''
Click here to see answer by Theo(3464)

Question 469183: What number less than 5 is to 39

Click here to see answer by Alan3354(30993)

Question 469239: The question is: A poker deck consisting of 52 cards, representing 13 denomination and 4 suits. A 5 card hand is called a flush if all cards are the same suit but not all 5 denominations are consecutive. You have drawn a 2 of hearts,3 of hearts, 7 of hearts, jack of hearts and a queen of hearts. Let N be the set of 5 cards in hearts that are not flushes. How many outcomes are in N?
I am assuming we need to find the probability of having a flush in hearts.
Card 1: .25, card 2:.24, card 3: .22, card 4: .20 and card 5: .19.
.25*.24*.22*.20*.19=.0005016
I don't know my next steps.
Click here to see answer by edjones(7569)

Question 469226: Please help me to solve: Suppose that 2 cards are dealt from a standard 52-card poker deck. Let A be the event that the sum of the 2 cards is 8(assume that aces equal 1) How many outcomes are in A?
This is how I started: Combinations that equal 8: A+7, 2+6, 3+5, 4+4, 5+3, 6+2, 7+A. Considering there are 4 cards for each number and add them together is 8 cards per set of combinations. There are 7 combinations, so 7*8=56. How does that sound?
Click here to see answer by edjones(7569)

Question 469218: I have a few problems similar to this and need some direction in solving them please!
a marketing firm asked a random set of married and single men as to how much they were willing to spend for a vacation. At a = .05, is there a difference in the two amounts?
sample size married 50, single 70
mean spending married 260, single 185
sample variance married 4500, single 9000
provided answers:
A) yes, because the test value 5.07 is outside the interval (-1.96, 1.96)
B) no, because the test value 2.00 is outside the interval (-1.96, 1.96)
C) no, because the terst value 0.34 is inside the interval (-1.96, 1.96)
D) yes, because the test value 2.00 is inside the interval (-1.96, 1.96)

Click here to see answer by edjones(7569)

Question 469290: Decide if events are mutally exclusive.
Event A: Randomly selecting someone who plays an instrument.
Event B: Randomly selecting a female
Are the events mutally exclusive
Click here to see answer by solver91311(16897)

Question 469291: What is the concept of 2 to 5 odds and the probability
example
there is a 2 to 5 odds that we will win the lottery, what is the probability that we wont? and that we will?
Click here to see answer by edjones(7569)

Question 469288: Requesting help on the three problems listed below:
1. A bag contains five cards: the jack, queen, king, ace and ten of clubs. Two cards are to be selected at random without replacement. List the sample space. Find the probability that one of the cards selected is the king.
2. The Cat Lovers' Club has nine members. They need to form a committee consisting of four members to judge the cat show. How many different committees are possible?
3. Two dice are rolled. What is the probability of rolling doubles?
Thanks in advance!!!
Click here to see answer by edjones(7569)

Question 469350: need help with a different type of problem. here they are:
for the sample summarized below, test the hypothesis at a = .05 that the two variances are equal. sample A variance 19, number of data values 8. sample B variance 9, number of data values 18.
A) reject the hypothesis because the test value 2.11 is less than the critical value 3.16.
B) reject the hypothesis because the test value 4.46 is greater than the critical value 3.01
C) do not reject the hypothesis because the test value 2.11 is less than the critical value 3.16
D) do not reject the hypothesis because the critical value 3.01 is greater than the test value 4.46
I have a few like this and could use the help. My last experience with this site was great! work was shown and it allowed me to solve the remainder of similar problems. Thanks in advance.
Click here to see answer by stanbon(57409)

Question 469323: USA Today reports that about 25% of all prison parolees become repeat offenders. Alice is a social worker whose job is to counsel people on parole. Let us say success means a person does not become a repeat offender. Alice has been given a group of four parolees.
(a) Find the probability P(r) of r successes ranging from 0 to 4. (Round your answers to three decimal places.) P(0) = 1
P(1) =
P(2) =
P(3) =
P(4) =
(b) Make a histogram for the probability distribution of part (a).
Click here to see answer by edjones(7569)

Question 469320: Suppose that a random sample of nineteen recently sold houses in a certain city has a mean sales price of $300,000 , with a standard deviation of $8000 . Under the assumption that house prices are normally distributed, find a 95% confidence interval for the mean sales price of all houses in this community.
What is the lower limit of confidence level?
What is the upper limit of confidence level?
Click here to see answer by stanbon(57409)

Question 469318: Suppose that a random sample of nineteen recently sold houses in a certain city has a mean sales price of , with a standard deviation of . Under the assumption that house prices are normally distributed, find a confidence interval for the mean sales price of all houses in this community.
What is the lower limit of confidence level?
What is the upper limit of confidence level?
Click here to see answer by stanbon(57409)

Question 469242: I have read my text more than once, googled help, and have talked to my teacher but this is still like learning another language to me.
A). How can standardized z- scores be used to compare people across different contexts, such as the batting averages of 2 players - one who played in the 1970s and one who played in the 1970s?
B). Z-Scores are standard scores whereas t-scores are standardized scores. Compare and contrast the similarities and differences between the 2 scores and explain when and why you would use each
Click here to see answer by stanbon(57409)

Question 469386: There are three brands of riding mowers: Ranger, Turfmaster, and Colt. Fifity percent of the riding mowers sold by a company are rangers, thirty five percent are turfmasters, and fifteen percent colts. Each brand of mower comes with a one-year parts and labor warranty. Based on their records, Perry knows that the chance of a warranty claim is 5% for the Ranger, 15% for the Turfmaster, and 25% for the Colt. If the company's manager tells a guy that a riding mower has just been brought in for a repair covered by the warranty, then
a) What is the chance that the riding mower is a Colt?
b) What is the chance that the riding mower is a Turfmaster?
c)What is the chance that the riding mower is a Ranger?
What confuses me are the two different percentages..how do I use the information?Also, yes there is a similar question to this posted on the website but no one has answered it yet so I posted this again. Thank you for your help.
Click here to see answer by stanbon(57409)

Question 469391: I am not wanting someone to do my work for me on this question that is why I didn't post any data. I am just not sure how to convert to the z-score.
With 25 subjects, how do I convert each age and height into a z-score?
Click here to see answer by jim_thompson5910(28598)

Question 469414: six circles numbered one thru 6
1 is yellow
2 is green
3 is orange
4 is orange
5 is orange
6 is yellow
assume that one cirlce is selected at random and each circle is equally likely to be selected. Determine the probability of selecting a 3, given that the circle is yellow.
how would I finish this? I just don't know how to work the problem out?
P=(3|yellow) my answer is 1/6 for selecting a 3 and 0 probability for selecting a yellow.
Click here to see answer by ccs2011(207)

Question 469405: Can someone please show me how to solve this statistic? Thank you!
Does crime pay? The FBI Standard Survey of Crimes showed that for about 80% of all property crimes (burglary, larceny, car theft, etc.), the criminals are never found and the case is never solved. Suppose a neighborhood district in a large city suffers repeated property crimes, not always perpetuated by the same criminals. The police are investigating three property crime cases in this district.
1.What is the probability that none of the crimes will ever be solved? (Use 3 decimal places.)
2.What is the probability that at least one crime will be solved? (Use 3 decimal places.)
3.What is the expected number of crimes that will be solved? What is the standard deviation? (Use 2 decimal places.)

Click here to see answer by ccs2011(207)

Question 469398: Can someone please with this one.
A board game uses the deck of 20 cards shown. 4 rows of cards and they are from 1-5.

firt row - 1,2,3,4,5
second row - 1,2,3,4,5
thrid row - 1,2,3,4,5
fourth row - 1,2,3,4,5
Two cards are selected at random from this deck. Determine the probability of they both show even numbers
a) with replacement
b) without replacement

Click here to see answer by ccs2011(207)

Question 469433: how much 20% acid must be added to 3000 ml of a 50% soltion to create a 25% solution. How much solution will be created?
Click here to see answer by ccs2011(207)

Question 469509: . If there are 16 total bottles of diet soda, 8 total bottles of regular soda, and 4 total bottles of water, what is the probability of each of the following:
(i) Choosing a bottle of diet soda when a bottle is chosen at random
(ii) Choosing a bottle of regular soda when a bottle is chosen at random
(iii) Choosing a bottle of water when a bottle is chosen at random
**Answers I came up w/ are below not sure if they are correct**
i) 2/3
ii) 1/3
iii) 1/6

Click here to see answer by ewatrrr(10682)

Question 469552: Round each of the following number to 2 decimal places
(a) 3.14501
(b) 0.0449
(c) 0.0961

Click here to see answer by Tatiana_Stebko(1326)

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