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Question 608494: A company with 3000 employees requires that computer passwords consist of 4 digits followed by 3 letters. Each password cannot repeat a letter or number, and no password can be repeated. Passwords must be changed, by the employees, at the beginning of each month. To the nearest year, how many years of passwords exist?

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Question 608437: HI,
i would really appreciated if you can help me with this word problem:
The Student Life Committee asks that 2 members from a service club attend the next committee meeting. The 2 students will be selected from one of the following service clubs: Alpha Club with 22 members; Beta Club, 19 members; Gamma Club 25 members: and Zeta Club, 14 members. In how many ways can the 2 students be selected.
~Thanks G.Q
Click here to see answer by lynnlo(4176)

Question 608516: There are 67 students in a chemistry class. The instructor selects a student at random.
Students in a Chemistry Class
Males Females
Freshmen 10 15
Sophomores 13 3
Juniors 3 5
Seniors 2 16
a) What is the probability that he chooses a sophomore or a female?

b) What is the probability that he chooses someone who is male and a junior?

c) If a female is selected at random what is the probability that she is a freshmen?

Click here to see answer by ewatrrr(24785)

Question 608537: there are 7 players. Can more teams of 2 different people or 5 different people be formed?
Click here to see answer by stanbon(75887)

Question 608599: Six female students and five male students are nominated for scholarships. Only 3 scholarships will be awarded. If all 11 students are equally qualified what is the probability that all the scholarships are given to females? You may assume each candidate can receive a maximum of one scholarship.
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Question 609003: If A, B, C, D, E, F, and G are letters, how many different 4-letter words can be formed if repitition is allowed?
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Question 609021: I divide my class into 2 equal-sized groups alphabetically by last name. What is the likelihood that Richard Dirksing and Bill Peterson will be in the same group?
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Question 609065: How many different ID cards can be made if there are 6 digits on a card and no digit can be used more than once?
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Question 609067: An investigative agency has 7 cases and 5 agents. How many different ways can the cases be assigned if only one case is assigned to each agent?
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Question 609330: what is the value of nCr when n-r=1
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Question 609327: what is the value of nCr when r=n
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Question 609573: In how many ways can a president,vice president, an secretary be arranged from a club of 27 people?
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Question 609719: on the following dartboard, the radius of the bulls-eye (areaA) is 4 inches. the radius of each concentric circle is 4 inches more than the circle inside it. if a person throws randomly onto the dartboard, what is the probability that the dart will hit in area b?
Click here to see answer by Earlsdon(6294)

Question 609767: how many 6-digit numbers contain no 1's or 2's?
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Question 609892: Please help me on this problem! : There are 3 girls and 5 boys. how many possible ways are there when 3 girls go first and the rest of people can go which ever order they want?
Click here to see answer by stanbon(75887)

Question 609904: how many ways are there to form a group of 5 students out of a class of 25?
Click here to see answer by jim_thompson5910(35256)

Question 609905: How many 5 letter codes can be made with the letters in the word "market" if the letters can repeat within a code, and the first letter must be a vowel.
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Question 610198: Student ID codes consist of uppercase letters as well as the digits 0 through 9.
How many 2-character ID codes are possible if at least one of the digits must be a number?
Click here to see answer by Alan3354(69443)

Question 610242: please simplify the the expression completely (n!n^2-n!)/((n-1)(n+1))
I tried to simplify it, and all I could get was n(n-2)!n^2-n(n+2)!
Click here to see answer by jim_thompson5910(35256)

Question 610590:
Find the number of ways to purchase 5 different kinds of drinks from a selection of 13 drinks
Click here to see answer by jim_thompson5910(35256)

Question 610605: 10 people are to be divided into 3 committees, in such a way that every committee must have at least one member. and no person can serve on all three committees. In how many ways can this be done.
Click here to see answer by AnlytcPhil(1806)

Question 610904: Choose one of the letters A,B,C, or D and one of 5 numbers.
Click here to see answer by solver91311(24713)

Question 610992: How many different committees of 5 people can be formed from a group of 12 volunteers? Is that a permutation or combination?
Click here to see answer by ashipm01(26)

Question 611073: There are 5 students sitting around a table. How many different pairs of students could be formed from those students? I think it is 10
Click here to see answer by scott8148(6628)

Question 611213: how many cards must be selected from a standard deck to be sure of getting at least one red card?
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Question 611256: You have four different colored pencils. You give them away to four different people. How many possible combinations can there be?
Click here to see answer by jim_thompson5910(35256)

Question 611286: I'm really confused about permutations, and especially this problem!
"Flags of 6 countries are to be displayed in a row. The flags of two countries, A and B, must be next to each other.
a) In how many ways can this be done if the flag of country A must be to the left of the flag of country B?
(The answer key says 120, but I don't understand how)
b) In how many orders can the flags be displayed if the 2 flags can be in either order?
(The answer key says 240 but I don't understand how)"
Thank you so much!
Click here to see answer by jim_thompson5910(35256)

Question 611432: How many teams of two can I make from six kids
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Question 611430: How many 3person teams can be formed from6 people
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Question 611769: If you choose one boy out of 9 boys and one girl out of 16 girls, how many ways can this be done?
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Question 611961: How many solutions does the equation x1+x2+x3=8 have such that x1,x2, and x3 are integers, x1 ≥ 1, x2 ≥ 0, x3 ≥ 2.
Click here to see answer by richwmiller(17219)

Question 611967: please help.
Katarina has nine pairs of shoes to arrange in her closet. Assuming that she doesn't separate the pairs, how many different arrangements can she make?
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Question 612005: a student is asked to answer 8 out of 10 questions on exam. How many ways can a queston be answered?
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Question 612007: A club with 34 members is to select 5 officers ( president, vice president, treasure, secretary, historian) In how many ways can this be done?
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Question 611995: how many ways can 10 books be arranged on a bookshelf
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Question 611998: a lock has 3 tumblers and each tumbler can assume 5 positions. how many different possibilities are there.
Click here to see answer by rfer(16322)

Question 612059: How many different ways can three CDs be chosen from a case of 10 CDs?
Click here to see answer by richwmiller(17219)

Question 612094: how many ways can five airplanes be arranged on a runway?
Click here to see answer by jim_thompson5910(35256)

Question 612173: How many arrangements of the word CHORD can be made that begin with either an H or an O?
Click here to see answer by richwmiller(17219)

Question 612215: A bookself has space for 6 books. If 8 different books are available, how many different arrangements can be made on the shelf?
My answer was 28. I found this by using the following combination:
(8 nCr 6) = 28
I was marked wrong, what is the correct way to do this problem and how can i avoid this mistake in the future?
Click here to see answer by stanbon(75887)

Question 612196: The contractor wants to plant six oak trees, nine maple trees, and five poplar trees along the subdivision street. The trees are to be evenly spaced. In how many distinguishable ways can they be planted?
I got this far:
20!/(6!9!5!) = 77,597,520
I need to know the break down of this equation to get the answer.
Click here to see answer by Edwin McCravy(20054)

Question 612345: how many different 5 player teams can be made from a group of 12 people?
Click here to see answer by alicealc(293)

Question 612337: If you guess on three multiple choice questions where A,B,C,D are the only options, what are your chances of getting those three answers correct.
Click here to see answer by flame8855(424)

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