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Question 365753: From a group of 10 boys and 12 girls, a committee of 4 students is chosen at random. How many four-person committees containing at least 1 girl are possible?
Click here to see answer by sudhanshu_kmr(1152)

Question 365595: mark can remember only the first 3 digits of his friends phone number, he also know that the number has 7 digits and that the last digit is not a 0. If mark were to dial all of the possible numbers and if it takes him 23 seconds to try each one, how long would it take it to try every possibility?
Click here to see answer by sudhanshu_kmr(1152)

Question 365528: A committee of 10 is to be chosen from 9 women and 6 men.In how many ways can it be done if at least 4 men are to be on the committee?
Click here to see answer by sudhanshu_kmr(1152)

Question 366458: Using permutations, how do we solve this problem: How many distinguishable 6 letter "words" can be formed using the letters in LONDON? the answer is 180, but I can't figure out how to solve it. Please help.
Click here to see answer by robertb(5830)

Question 366488: Mrs. Grasso�s eleventh-grade class has 12 boys and 14 girls. In how many ways can
at least 2 boys be selected for a committee of 3 students?
(A) 66 (B) 286 (C) 924 (D) 1,144 (E) 4,004
Click here to see answer by sudhanshu_kmr(1152)

Question 365510: 9 basketball players are trying out to be on a newly formed basketball team. Of these players, 5 will be chosen for the team. If 6 of the players are guards and 3 of the players are forwards, how many different teams of 3 guards and 2 forwards can be chosen?
Click here to see answer by sudhanshu_kmr(1152)

Question 366796: How many ways can a row of four girls followed by four boys be arranged if the
girls must sit together and the boys must sit together?
(A) 16 (B) 256 (C) 576 (D) 10,080 (E) 40,320
Click here to see answer by amoresroy(361)

Question 366817: 5)In how many ways can 12 students be divided into three groups of 4, if the order of the groups and the arrangement of the students in a group are immaterial ?

Click here to see answer by stanbon(75887)

Question 366814: 3)In how many ways can 20 people be seated in 30 chairs

Click here to see answer by stanbon(75887)

Question 366812: 1)In how many ways can 12 students be divided into three groups of 4,if the order of the groups and the arrangement of the students in a group are immaterial ?

Click here to see answer by amoresroy(361)

Question 366931: How many ways can we select a president, vice-president and secretary from a group of eight people?
I used 8C3 and came up with 56. Is this correct?
Click here to see answer by jim_thompson5910(35256)

Question 366816: 4)Eight policemen are to be posted to guard three separate buildings.
In how many ways may they all be posted if no building is to be guarded by less than two policemen?

Click here to see answer by robertb(5830)

Question 367036: in how many number of ways can 7 men and 7 women sit in a round table such that no two women sit together?
Click here to see answer by sudhanshu_kmr(1152)

Question 366813: 2)In how many ways can 3 different Mathematics, 2 different Physics and 4 different Chemistry books be arranged on a shelf if
A) the Mathematics books are next to each other,
B)the books are kept in subject groupings?

Click here to see answer by sudhanshu_kmr(1152)

Question 367067: Hi, Please help!
There are 21 English books and 19 French Books. How can these books be arranged on a shelf where no 2 french books are placed together?
Click here to see answer by Jk22(389)

Question 367377: In how many ways can a mother distribute three different toys among her seven children if a child may receive anywhere from 0 to 3 of the toys?
Click here to see answer by robertb(5830)

Question 367378: A club has 18 members, 10 men and 8 women. In how many different ways can they select a committee of 5 from their members?
Click here to see answer by robertb(5830)

Question 367385: In how many different ways can the letters of the word BERIBERI be arranged?
Click here to see answer by edjones(8007)

Question 368260: Quality Control: A factory produces fuses, which are packaged in boxes of 10. Three fuses are selected at random from each box for inspection. The box is rejected if at least one of these three fuses is defective. What is the probability that a box containing five defective fuses will be rejected?
The answer is 11/12 which = .917, but how is it done?
Thank you in advanced...
Click here to see answer by robertb(5830)

Question 368929: 12 boys and 10 girls in which seven students are chosen to go to the blackboard. What is the probability that at least 2 girls are chosen?
C(22,7) = 170,544
I know the answer to this one is 16/17 but how?
I did the long way, need the short way
Long way:
7 b 0g C(12,7) * C(10,0) = 792
6 b 1g C(12,6) * C(10,1) = 9,240
etc...
How do I do the answer in the below format:
C(#,#) C(#,#)
-------------
C(22,7)
A question that relates to the above:
What is the probability that no boys are chosen?
What is the probability that more boys than girls are chosen?
What is the probability that the first three children chosen are boys?

Click here to see answer by Edwin McCravy(20054)

Question 368924: Rotten Tomato: A bag contains 9 tomatoes, of which 1 is rotten. A sample of three tomatoes is selected at random. What is the probability that the sample contains the rotten tomato?

Click here to see answer by Alan3354(69443)

Question 368927: Coin Tosses: A coin is to be tossed six times. What is the probability of obtaining exactly three heads?
Click here to see answer by sudhanshu_kmr(1152)

Question 369285: IN HOW MANY WAYS CAN I DIVIDE 5 PEOPLE INTO 3 GROUPS OF 2,2,AND 1, REGARDLESS OF ORDER ?
Click here to see answer by robertb(5830)

Question 369402: A test consists of 10 true-or-false questions. If a student randomly chooses answers for each question, fin the probability that the student:
Answers at least 1 question correctly. (3 decimals)
I got 2^10 = 1,024
I did this way, but does not work, very close...
C(10,1)/1024 =
10/1024 = .00976

The answer is 0.999 but how?

Click here to see answer by tanmike(1)

Question 369499: 4 + -2 < 6 + -2

Click here to see answer by Alan3354(69443)

Question 369622: A test consists of 10 true-or-false questions. If a student randomly chooses answers for each question, find the probability that the student:
Answers at least 1 question correctly. (3 decimals)
I got 2^10 = 1,024
I did this way, but does not work, very close...
C(10,1)/1024 =
10/1024 = .00976
The answer is 0.999 but how?

Click here to see answer by Fombitz(32388)

Question 368468: A committee of 5 people is selected from a group of 8 men and 9 women. In how many ways can the committee be selected so it contains at least one woman?
Click here to see answer by edjones(8007)

Question 369747: Aunt Rose has a children's table for Thanksgiving dinner. There are 4 children. For chairs she has a small bean bag, a small rocking chair, a stool, and a little desk chair. How many different ways could she seat those 4 children at the table?
Click here to see answer by edjones(8007)

Question 369960: Computers manufactured by a certain company have a serial number consisting of a letter of the alphabet followed by a six-digit number. If all the serial numbers of this type have been used, how many sets have already been manufactured?

Click here to see answer by Fombitz(32388)

Question 370106: Of the 42 students in algebra 2 taking a certain test; 8 made a's, 11 made b's, 15 made c's, 5 made d's and the rest made f's. What is the probability that a student chosen at random did not make a C?
Click here to see answer by robertb(5830)

Question 370261: what are all of the possible combinations that can be made of 4 digits using numbers 0-9?
Click here to see answer by edjones(8007)

Question 370362: There are 4 slots, each containing any of letters l, g, r, i.
What are the odds that letters stored in these slots read the word girl

Click here to see answer by Fombitz(32388)

Question 370342: a. Suppose we have a group of 8 students sitting on a long bench.
Four of the eight insist on sitting side-by-side. In how many ways can the eight students be seated on the bench?

b. Two of the eight insisting on not sitting side by side. In how many ways can the eight students be seated on the bench?
thanks alot
Click here to see answer by stanbon(75887)

Question 370639: I have to arrange 5 people around a rectangular table, but Max and Suzie must sit together. How many ways do I have of arranging these people?

Click here to see answer by jim_thompson5910(35256)

Question 371655: How many three-letter words can be made from the first eight letters of the alphabet if consonants cannot be next to each other and letters cannot be repeated?
Click here to see answer by amoresroy(361)

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