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Question 635096: A manufacturer of mainframe computers is trying to win a large contract with his client. The manufacturer is going to send to the client's facilities 5 salespersons, 7 technicians, and 3 software engineers. In how many ways can these 15 people be selected if the manufacturer has available 10 salespersons, 9 technicians, and 7 software engineers?
Click here to see answer by ewatrrr(10682)

Question 635095: A pizza restaurant offers a combination pizza consisting of any three of the four ingredients: pepperoni (P), mushrooms (M), sausage (S), and anchovies (A). Determine the number of possible combination pizzas.
Click here to see answer by ewatrrr(10682)

Question 635092: The environmental protection agency must investigate ten mills for complaints of air pollution. How many different ways can a representative select five.of these to investigate this week?
Click here to see answer by ewatrrr(10682)

Question 635069: The participants at a large convention are offered 7 sightseeing tours on each of 4 days. In how many ways can a person arrange to go on one of these tours?
Click here to see answer by ewatrrr(10682)

Question 635066: From 4 red, 5 green, and 6 black ball pens, how many selection of 9 ball pens are possible if 3 of each color are to be selected?
Click here to see answer by ewatrrr(10682)

Question 635063: A developer of a new subdivision offers a prospective home buyer a choice of 4 models, 3 different lot sizes, a garage or carport, and a patio or screened porch. How many different plans are available to this buyer?
Click here to see answer by ewatrrr(10682)

Question 635064: a. How many ways can 6 passengers be lined up to get on a train?
b. If a certain persons insist on following each other, how many ways are possible?
Click here to see answer by ewatrrr(10682)

Question 635123: 6. If we randomly select 2 diskettes, one after the other , from a box containing a diskettes of which 3 are unformatted,
a. What is the probability that both of them will be unformatted?
b. What is the probability that both of them will be formatted?

Click here to see answer by ewatrrr(10682)

Question 635056: With Solution Please....
From a box containing 5 blue balls and 3 green balls, 3 balls are drawn in succession. What is the probability that all 3 are of the same color if:
a. there is replacement?
b. there is no replacement?
Click here to see answer by ewatrrr(10682)

Question 635031: The average math SAT score is 516 with a standard deviation of 117. A particular high school claims that its students have unusually high math SAT scores. A random sample of 45 students from this school was selected, and the mean math score was 549. Is the high school justified in its claim? Explain.
Yes or No, because the z-score (??) is usual or unusual since it lies or does not lie within the range of a usual event, namely within 1, 2 or 3 deviation(s).
Please help answer the questions and find the z-score.
Click here to see answer by ewatrrr(10682)

Question 635161: A surgical technique is performed on eight patients. You are told that there is an 80% chance of success.
a) Construct a binomial distribution.
b) Find the mean, variance, and standard deviation of the probability distribution.
c) Find the probability that the surgury is successful for exactly six patients.
d) Find the probability that the surgury is successful for fewer than six patients
Click here to see answer by ewatrrr(10682)

Question 635168: A shop offers 17 varieties of bagels, 28 flavors of cream cheese, and 24 flavors of coffee. How many different orders for a bagel, cream cheese, and a coffee can a customer place?
thank you so much.
Click here to see answer by ewatrrr(10682)

Question 635149: A description of different houses on the market includes the following three variables. Which of the variables is quantitative?
A. the square footage of the house
B. the monthly gas bill
C. the monthly electric bill
D. all of the above

Click here to see answer by ewatrrr(10682)

Question 635146: A company has three divisions and three conference rooms for meetings. To keep track of the use of their facilities, for each meeting held in the company, the division holding the meeting is recorded, the room for the meeting is recorded, and the length of time of the meeting is recorded. Which of the variables is quantitative?
A. the division holding the meeting
B. the conference room for the meeting
C. the length of time for the meeting
D. all of the above

Click here to see answer by ewatrrr(10682)

Question 635420: Twenty-six small communities in Connecticut (population near 10,000 each) gave an average of x = 138.5 reported cases of larceny per year. Assume that σ is known to be 44.5 cases per year.
(a) Find a 90% confidence interval for the population mean annual number of reported larceny cases in such communities. What is the margin of error? (Round your answers to one decimal place.)
lower limit =
upper limit =
margin of error =
(b) Find a 95% confidence interval for the population mean annual number of reported larceny cases in such communities. What is the margin of error? (Round your answers to one decimal place.)

lower limit =
upper limit =
margin of error =
(c) Find a 99% confidence interval for the population mean annual number of reported larceny cases in such communities. What is the margin of error? (Round your answers to one decimal place.)
lower limit =
upper limit =
margin of error =

Click here to see answer by ewatrrr(10682)

Question 635427: Suppose that an experiment is repeated four times. A certain event has probability 1/10 in a single repetition of the experiment. What is the probability that it never occurs?
Click here to see answer by ewatrrr(10682)

Question 635451: Can someone let me know if i'm on the right track here?
A bag contains 8 green, 4 red, 5 yellow, and 6 blue marbles. Four marbles are drawn from the box at the same time.
A. What is the probability that all four are the same color?
B. What is the probability that none of the marbles are blue?
C. What is the probability that you get one marble of each color?
D. What is the probability that you draw more than 2 green?
I'm not sure if I am on the right track here or not...
A. P(all same color) = 8C4+4C4+5C4+6C4/23C4 = 91/8855
B. P (non are blue) = 17C4/23C4= 2380/8855
C. P (one of each) = 8*4*5*6/23C4 = 960/8855
D. P (More than 2 green) = 8C3*15C1=840 (3 yellow)
8C4*15C0=70 (4 yellow)
840+70/23C4= 910/8855
Any help would be greatly appreciated
Click here to see answer by ewatrrr(10682)

Question 635612: What percentage of the area would the Empirical Rule say is between z = -3.00 and z = +3.00?
Click here to see answer by reviewermath(500)

Question 635668: 5. chap 10 The manufacturer of the X-15 steel-belted radial truck tire claims that the mean mileage the tire can be driven before the tread wears out is 60,000 miles. The standard deviation of the mileage is 5,000 miles. The Crosset Truck Company bought 48 tires and found that the mean mileage for their trucks is 59,500 miles. Is Crosset's experience different from that claimed by the manufacturer at the .05 significance level?
6. chap 10 The MacBurger restaurant chain claims that the waiting time of customers for service is normally distributed, with a mean of 3 minutes and a standard deviation of 1 minute. The quality-assurance department found in a sample of 50 customers at the Warren Road MacBurger that the mean waiting time was 2.75 minutes. At the .05 significance level, can we conclude that the mean waiting time is less than 3 minutes?

Click here to see answer by reviewermath(500)

Question 635778: Can someone check my work on this problem?
City Pizza makes a specialty pizza with 4 layers of toppings alternating with layers of cheese and advertises that they offer 26 different toppings.
A) How many different pizzas can be made if none of the toppings can be duplicated and the order of the toppings matters?
26*25*24*23 = 358,800
B) How many different pizzas can be made if none of the toppings can be duplicated and the order of toppings doesn't matter?
26!/4!(26-4!)=14,950
Any help would be great, thank you so much
Click here to see answer by solver91311(16868)

Question 635787: An unfair coin comes up heads 52.7% of the time. The coin is flipped a total of 19 times.
A) what is the probability you get exactly 12 heads?
(19C12)(.527)^12(.473)7= .1335 (not sure if correct)
B) What is the probability that you get exactly 11 tails?
(19C11)(.473)^11(.527)^8= .1338 (again not sure)
C) What is the probability that you get at most 16 tails?
Any help would be great. thank you so much
Click here to see answer by ewatrrr(10682)

Question 635791: Please help, this problem is driving me crazy!
An exam has 30 questions and students need to answer 20. How many ways can this be done if the first 5 and exactly 6 of the last 8 questions must be answered and question #13 must be skipped?
Thank you for your help!
Click here to see answer by stanbon(57214)

Question 635808: please help check and explain!
Dealt 6 cards from a 52 card deck
A. Probability you are dealt no spades and exactly 2 sevens?
I tried (3C2)(39C4/52C4=246753/270725=.9115
B. Probability that you are dealt no more than 1 jack?
I came up with..
(48C6)+(4C1)(48C5)/52C6=.9392
C. Probability that you are deal at least 2 hearts and at least 2 clubs?
I am really struggling with this one..I think its something along the lines of
(4C2*4C2*44C2)+(4C3*4C3*44C2)/52C6
Any help would be awesome.
Click here to see answer by ewatrrr(10682)

Question 635733: Suppose Z is a standard normal variable and P( Z>c)=0.0154, the value of c is?
Click here to see answer by stanbon(57214)

Question 635860: The letters of the word HONESTY are written on slips of paper, and are placed in a box. A slip of paper is chosen at random. What is the probability that:
a. the letter is a vowel?
b. the letter is a consonant?
c. the letter is H?

Click here to see answer by nerdybill(6948)

Question 635908: Please help I am so confused!!!
I have to do a two-tailed hypothesis test, using a 0.5 significance level: I have to use the intrinsic by gender which is 1-Male (38) and 2 -Female (27). I have to state the null and an alternate statement for the test, I have to identify the significance level, the test statistic, and the critical value. I also have to state whether I am rejecting or failing to reject the null hypothesis staement. Last but not least I have to explain how the results could be used by the manager of the company.
Click here to see answer by stanbon(57214)

Question 636115: A delicatessen offers 4 different breads, 4 cheeses, and 6 different meats. In how many ways can a
sandwich be made with 1 bread,1 cheese and 2 meats?
Click here to see answer by ewatrrr(10682)

Question 636129: Please help. Completely lost...
In how many ways can the letters in the word TRANSPORTATION be arranged if the first letter must be an A and the last letter must not be a T?
Would really appreciate it
Click here to see answer by jim_thompson5910(28476)

Question 636114: A pizza place offers 3 different cheeses and 8 different toppings. In how many ways can a pizza be made with 1 cheese and 3 toppings?
Click here to see answer by ewatrrr(10682)

Question 636131: A random number is generated between 0 and 100 on one try.
To "win" the number must be 10 or below.
I can try multiple times.
Doesn't the probably increase the more times I "try"?
Can a formula be put to that?
Thanks!

Click here to see answer by Alan3354(30952)

Question 636296: in a class consisting 18 boys 22 girls , one student is absent . the probability that the absent student is a boy
1)9/20
2)11/20
3)1/2
4)1/4
Click here to see answer by reviewermath(500)

Question 636272: I must perform a two-tailed hypothesis test using a .05 significant level intrinsic by gender which there are 39 males and 27 female. I need to state the null and a alternative statement for the test. I need to identify the significant level, the test statistic, and the critical value. I need to explain weather rejecting or failing the null hypothesis statement.
Click here to see answer by stanbon(57214)

Question 636117: 9 character password has four numbers (from 1 to 7) followed by two letters (from A to Z) followed by three more numbers (from 1 to 7).
A) How many different passwords can be formed?
B) How many different passwords have no repeated letters or numbers?
would this be 26*7?
Any help would be greatly appreciated. thank you
Click here to see answer by stanbon(57214)

Question 636271: Help,
The diameters of grapefruits in a certain orchard are normally distributed with a mean of 7.30 inches and a standard deviation of 0.80 inches.
(A) What percentage of the grapefruits in this orchard have diameters less than 6.7 inches?
(B) What percentage of the grapefruits in this orchard are larger than 7.20 inches?
Click here to see answer by stanbon(57214)

Question 636317: A 4 sided die is rolled, a 1 occurs 27.2% of the time, a 2 occurs 26.3% of the time, a 3 occurs 23.1% of the time, and a 4 occurs 23.4% of the time.
Find E(X)?
would this be 1(.272)+2(.263)+3(.231)+4(.234)?
Please help! thank you so much
Click here to see answer by ewatrrr(10682)

Question 636369: you randomly select one card from a 52-card deck. Find the probability of selecting a red eight or a red six
Click here to see answer by jim_thompson5910(28476)

Question 636456: If a computer code contains 2 letters and 3 numbers and none can repeat, how many combinations are possible?

I am thinking:
26*25*24...*1*25 PLUS 9*8*7...*1*8*7. Would that be correct for the formula?
Thank you!
Jama
Click here to see answer by KMST(1860)

Question 636562: If the random variable z is the standard normal score and a > 0, is it true that P(0 < z < a) = 1 - P(z < a)? Why or why not?
Click here to see answer by ewatrrr(10682)

Question 636571: Find the area under the standard normal curve for the following:
(A) P(z < -0.68)
(B) P(0 < z < 1.02)
(C) P(-1.78 < z < 1.88)
Click here to see answer by ewatrrr(10682)

Question 636706: In a bag containing only blue, red and green marbles, all but 15 are blue, all but
13 are red and all but 12 are green. How many are red?
1. 13
2. 7
3. 25
4. 20
Click here to see answer by KMST(1860)

Question 636759: A bag contains 1 red ball, 2 green balls, 2 white balls, and 5 black balls. A random ball is removed and its color is recorded. The ball is returned to the bag, then another random ball is removed. What is the probability that the first ball is black and the second ball is not red?

Click here to see answer by ewatrrr(10682)

Question 636624: Assume that the average annual salary for a worker in the United States is $38,000 and that the annual salaries for Americans are normally distributed with a standard deviation equal to $7,000. Find the following:

(A) What percentage of Americans earn below $25,000?
(B) What percentage of Americans earn above $46,000?
Click here to see answer by ewatrrr(10682)

Question 636867: A sample of n=8 scores has a mean of 6. What is the value of ∑X for this sample?
Click here to see answer by stanbon(57214)

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, 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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