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Question 840576: Five persons, A, B, C, D, E, are going to speak at a meeting. In how many orders can they take their turns if B must speak after A?
Click here to see answer by ewatrrr(24785)

Question 839834: How many 3-letter codes can be formed with the letters A, B, and C if each letter can be used only once in the code?
Click here to see answer by Fombitz(32388)

Question 840933: a committee of 5 people must be selected from 5 men and 8 women. How many ways can a selection be done if there are at least 3 women on the committee?
Click here to see answer by ewatrrr(24785)

Question 840893: How many different words can be made from the letter in SOCCER if only 4 letters are used?
Click here to see answer by Edwin McCravy(20054)

Question 840911: 1. how many combinations of students are possible if the group is to consist of exactly 3 freshmen?
2.How many combinations of students are possible if the group is to consist of all members of the same class?
Click here to see answer by Edwin McCravy(20054)

Question 841039: A company wants to create unique ID numbers for each of its employees. The ID numbers are all five digits long. How many ID numbers can be created (HINT: How many options do I have for each digit?)
Click here to see answer by Fombitz(32388)

Question 841317: there were 3/5 as many men as women at a seminar. there were 48 fewer men than women what was the total number of en and women at the seminar?

Click here to see answer by ewatrrr(24785)

Question 841245: A munitions warehouse contains 71 bombs, of which 5 are defective. A sample of 10 bombs will be drawn and tested.
a. What is the probability that the sample will contain exactly 2 defective bombs?
b. What is the probability that the sample will contain less than 2 defective bombs?
Im trying to figure out what this question is. Im thinking its a hypergeometric distribution but i just need a little help with it because i dont know where to start.
Thank you in advance

Click here to see answer by edjones(8007)

Question 841542: Combinations
3. In how many ways can a group of 10 people be divided into (a) two groups consisting of 7 and 3 people (b) three groups consisting of 4,3 and 2 people?
[ans: (a) 120 (b) 12600 ]
Click here to see answer by Edwin McCravy(20054)

Question 841138: A group consists of 6 students (3 boys and 3 girls) and one teacher. In how many ways can the 7 people sit in a row if boys cannot sit together and girls cannot sit together?
Click here to see answer by Edwin McCravy(20054)

Question 841602: How many ways can three items be selected from a group of six items? Use the letters A,B,C,D,E, and F to identify the items, and list each of the different combinations of three items.
Click here to see answer by stanbon(75887)

Question 841604: How many different ways can 4 people be seated in a car with 7 seats?
(Assume one person must be driving at all times.)
Click here to see answer by richwmiller(17219)

Question 841645: A certain school's math team consists of 5 seventh-graders and 7 eighth-graders. they wish to choose 4 students for a CJML team round. how many such team are possible, given that the team can contain no more than 2 eighth-graders?
Click here to see answer by ewatrrr(24785)

Question 841400: A group of 8 teenagers are lined up to buy tickets to a rock concert. How many possible arrangements of teenagers are there?
Would it be 1*2*3*4*5*6*7*8 to equal 40320 different ways?
Click here to see answer by richwmiller(17219)

Question 841652: In how many ways can a committee consisting of 4 faculty members and 5 students be formed if there are 10 faculty members and 11 students eligible to serve on the committee?
Click here to see answer by richwmiller(17219)

Question 841541: Premutations
1. How many numbers consisting of five digits each can be made from the digits 1,2,3,.......,9 if (a)the numbers must be odd (b) the first two digits of each number are even. [ans: (a) 8400 (b) 2520]
2. Solve the proceeding problem if repetitions of digits are allowed.
Click here to see answer by Edwin McCravy(20054)

Question 839759: In a group there are 25 girls and 15 boys. In how many ways can we choose a team of 5
persons, with 3 girls and 2 boys?
Click here to see answer by Edwin McCravy(20054)

Question 842009: a contractor builds homes of 9 different models and presently has 3 lots to build on. In how many different ways can he arrange homed on this lot? assume 3 different models will be built
Click here to see answer by jim_thompson5910(35256)

Question 838890: How many distinct 4 digit numbers can be formed from 1, 1, 2, 2, 2, 3, 4? I have found many problems with one digit repeating that remove the repeated numbers by division, but I can't figure out what to do with 2 repeating digits aside from lists which are rather inefficient. (7*6*5*4)/(3! +2) is the closest to what I believe to be the answer.
Click here to see answer by Edwin McCravy(20054)

Question 842122: in how many ways four books of maths and three books of physics be placed on a shelf so that the books on the same subject are always together?please tell
Click here to see answer by ewatrrr(24785)

Question 842124: how many even numbers of four digit number can be formed from the digits 1,2,3,4,5,if repetition is permitted?please tell
Click here to see answer by ewatrrr(24785)

Question 842125: ther are 10 bulbs in a hall.each one of them can be switched on independently.in how many ways the hall can be illuminated?please tell
Click here to see answer by ewatrrr(24785)

Question 842134: 11 persons are required to pose for photograph. 5 of the 11 are required to pose in a swatting position in front of the remaining 6 who will pose standing. Determine the number of ways the group can pose if David and Barbara being senior citizens cannot pose squatting position?
Click here to see answer by ewatrrr(24785)

Question 842105: Solvetheequation(n+1)! 30(n−1)!forn∈N.
(Remember: N is the set of natural (whole non-negative) numbers.)
Click here to see answer by Fombitz(32388)

Question 842107: A committee of five is to be selected from a group of 12 children. The two youngest cannot both be on the committee. In how many ways can the committee be selected?
Click here to see answer by ewatrrr(24785)

Question 842106: A group of 15 students contains seven boys and eight girls. In how many ways
can a committee of five be selected if it must contain at least one boy?
Click here to see answer by ewatrrr(24785)

Question 842104: A committee of four children is chosen from eight children. The two oldest children cannot both be chosen. Find the number of ways the committee may be chosen.
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Question 842103: Ten people are to travel in one car (taking four people) and one van (taking six people). Only two of the people can drive. In how many ways can they
be allocated to the two vehicles? (The permutation of the passengers in each vehicle is not important.)
Click here to see answer by ewatrrr(24785)

Question 842187: how many different ways could four distinct days of the week be chosen so that atleast one of them begins with the letter T
Click here to see answer by ewatrrr(24785)

Question 842492: We are to seat 7 boys and 10 girls in a circular arrangement. In how many ways can this be done if no girl is to sit next to a girl?
Click here to see answer by josmiceli(19441)

Question 842502: number of the arrangements of the letters of the word EAMCET so that no two vowels are together is?please tell
Click here to see answer by Chaudhary007(1)

Question 842435: Four men and eight women are to line up for a picture with the four men in the middle. How many ways can this be done? (Assume there are four women on each side of the group of men)
Click here to see answer by Theo(13342)

Question 842491: We are to seat 10 boys and 7 girls in a circular arrangement. In how many ways can this be done if no girl is to sit next to a girl?
Click here to see answer by ewatrrr(24785)

Question 843013: how many groups are possible if 132 pens are eually distributed in gropups
Click here to see answer by aulii(13)

Question 843103: A committe consists of 10 Republicans and 16 Democrats. How many different sumbcomittees of 5 can be formed if the subcomittee must consist of 3 Republicans and 2 Democrats?
Click here to see answer by ewatrrr(24785)

Question 843193: There are 10 members on the Student Council. A committee consisting of 4 members is to be made. How many different committees are possible?
Click here to see answer by ewatrrr(24785)

Question 843160: A computer password consists of eight characters. Repetitions are allowed.
How many different passwords are possible if each character may be any lowercase letter or digit?
So this would be something along the line of 1/36*8? im not completely sure though.
Click here to see answer by Fombitz(32388)

Question 843244: In how many ways can the club choose a committee of 4 if the committee must have at least 1 girl on it?
Click here to see answer by ewatrrr(24785)

Question 843235: A music class of 5 girls and 4 boys is having a recital. If each member is to perform once,how many ways can the program be arranged in each of the following cases?
(A) all girls must perform first.
(B) A girl must perform first and a boy must perform last.
(C)Elsa and Doug will perform first and Last. Respectively.
(D) The entire program will alternate between boy and girl.
(E)The First, Fifth, and ninth performer must be girls.
I think it is combination.

Click here to see answer by Edwin McCravy(20054)

Question 843558: A committee of 7 people is to be chosen from a group of 9 managers and 6 accountants. The committee must include 4 managers and 3 accountants. How many different ways can the committee be chosen?
Click here to see answer by ewatrrr(24785)

Question 843631: committees of US Senators. How many different 5 member committees could be formed from the 100 US senators?
My work:
This is combination.
100C5
100!
-----------
5! (100-5)!
I get: 75287520
Did I do this right? Thanks!
Click here to see answer by ewatrrr(24785)

Question 843643: An ATM PIN consists of four digit chosen from 0-9, and repetition of a digit is allowed. How many PINs contain at least one "7"?
Click here to see answer by richard1234(7193)

Question 843630: window with 4 panes: how many ways can you paint one pane blue? How many ways can you pint two panes blue? I tried fundamental counting principle: 1 x 4 = 4 different ways, but I think only 6 ways to paint two panes and 2 x 4 is not 6. thanks for the help
Click here to see answer by richwmiller(17219)

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