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Question 907806: A certain website requires users to log on using a security password.
a. If the password must consist of 6 letters followed by 2 digits, determine the total number of possible distinct passwords.
b. If passwords must consist of 6 non-repetitive letters followed by 2 digits, determine the total number of possible distinct passwords.

Click here to see answer by ewatrrr(24785)

Question 907858: Social Security Numbers A Social Security number is used to identify each resident of the United States uniquely. The number is of the form xxx�xx�xxxx, where each x is a digit from 0 to 9.

(a)

How many Social Security numbers can be formed?

(b)

What is the probability of correctly guessing the Social Security number of the president of the United States?
Click here to see answer by Fombitz(32388)

Question 907871: A pollster randomly selected 4 of 10 available people.
How many different groups of four are possible?
Click here to see answer by Fombitz(32388)

Question 907648: How many different signals can be sent up on a flagpole if each signal requires
seven
blue and
seven
yellow flags and the flags are identical except for color?
Click here to see answer by Edwin McCravy(20054)

Question 908128: Seven passengers together enter an elevator on the first of an 11-floor building. Assume that the egress
pattern to floors 2, 3, � � �, 11 is the same. What is the probability that all get off at different floors?
Click here to see answer by Edwin McCravy(20054)

Question 908715: twenty points , no 3 of which are collinear, lie in a plane. Using these points, how many straight lines can be drawn

Click here to see answer by richard1234(7193)

Question 903151: "how many 7-digit numbers are there containing two 3s and three 8s if neither of the other two digits are 3 or 8( the first digit cannot be zero"
Click here to see answer by Edwin McCravy(20054)

Question 908101: How many ways can an IRS auditor select a group of 8 tax returns from a group of 21 tax returns for an audit?
Click here to see answer by Edwin McCravy(20054)

Question 908072: how many different teams of 5 children can be chosen from a group of 7 boys and 11 girls if each team must have at least 2 boys on it
Click here to see answer by Edwin McCravy(20054)

Question 908843: Show that:
n C r = [(n-2) C r] + 2[(n-2) C (r-1)] + [(n-2) C (r-2)]

Click here to see answer by Edwin McCravy(20054)

Question 908839: how many students must be in a room to be sure that at least twelve are boys or at least twelve are girls
Click here to see answer by Edwin McCravy(20054)

Question 908836: Can you please help me with this?
A modern Master combination lock is electronic and the combination consists of a series of up, down, left, and right clicks. The user-created combination can vary from 4-12 clicks. Again, order is important, and repetition is allowed. How many combinations are possible with a 4-click combination?
P = (n*4)r = (12*4)4 = 484 = 5,308,416 is what I tried.
Click here to see answer by Edwin McCravy(20054)

Question 908941: How many seven-digit telephone numbers are possible if the first two digits cannot be ones or zeros?
Click here to see answer by Edwin McCravy(20054)

Question 907939: How many different teams of 4 children can be chosen from a group of 19 girls and 17 boys if each team must have at least two boys in it?
I think it would be nCr(36,4)/[nCr(17,2)*nCr(17,3)*nCr(17,4)]
So you need teams of 4(numerator)
and you need a minimum of two boys so exhaust all combinations(denominator)
Click here to see answer by Edwin McCravy(20054)

Question 907713: HELP PLEASE!!!!
Q. Number of different ways in which 8 different books can be distributed among 3 students, if each student receives at least 2 books.
Click here to see answer by Edwin McCravy(20054)

Question 907414: zip code sequence of five digits were introduced by the united states post office department in 1963 how many zip codes are possible?zip codes for delaware, new york, and pennsylvania begin with the digit 1. how many such zip codes are possible?
I got 10^5 for the first part
Click here to see answer by Edwin McCravy(20054)

Question 908987: Have 30 songs and want to make cd with 12 songs on a cd how many combinations can i have using 30 songs and 12 to a cd
Click here to see answer by ewatrrr(24785)

Question 908970: in how many different ways can 4 boys and 3 girls be arranged in a row such that all boys stand together and all girls stand together
Click here to see answer by ewatrrr(24785)

Question 908876: 65. Randomly Playing Songs Suppose a compact disc (CD) you just purchased has 13 tracks. After listening to the CD, you decide that you like 5 of the songs. The random feature on your CD player will play each of the 13 songs once in a random order. Find the probability that among the first 4 songs played (a) you like 2 of them; (b) you like 3 of them; (c) you like all 4 of them.
Click here to see answer by ewatrrr(24785)

Question 908962: if one item is selected from each of the four groups,in how many ways can a meal be ordered?
Click here to see answer by Alan3354(69443)

Question 909208: If there are five (5) football teams and which could either win, lose or draw, how many combinations are there?
Click here to see answer by swincher4391(1107)

Question 909251: a group of 630 children is seated in row for a group photo session. each row contains three less children than the row in front of it which one of the following number of row is not possible??
a 2
b 3
c 5
d 6
Click here to see answer by Edwin McCravy(20054)

Question 909723: A school fundraiser charges $5 to play. Player flips a coin. If coin lands on Tails,the player looses and gets nothing. If coin lands on heads, player gets to flip a second time;player would then either win $5 plus gets $5 back if comes as heads or just $5 if tails.
What is the expected value of the payout in this game?
Click here to see answer by stanbon(75887)

Question 909806: I have 32 darts players they are in groups of 4 but playing as individuals,the groups of 4 needs to be different each week how do I work this out?
PS I am not that good at maths but the games due to start next week so any help would be great
Thanks for any help
Geoff

Click here to see answer by rothauserc(4718)

Question 909846: Suppose a class is containing 10 women and 7 men.
(a) In how many different ways can a team of 6 be chosen from the class?
(b) What if the team must contain exactly 4 women?
(c) What if the team must contain at least 4 women?
Click here to see answer by ewatrrr(24785)

Question 908932: Probability Of Drawing A Red Card On The First Drawn Replacing It And Drawing A Face Card On The Second Draw
Click here to see answer by Fombitz(32388)

Question 910222: i have 3 last problem.
Click here to see answer by richwmiller(17219)

Question 910219: find the number of permutations of the word thermometer. thanks! :)
Click here to see answer by Edwin McCravy(20054)

Question 910221: in how many ways can 9 persons be divided into 3 groups consisting of 4,3 and 2 persons?
Click here to see answer by Lenzky(18)

Question 910596: How many ways can a group of 12, including 4 boys and 8 girls be formed into 2 groups of 6
Click here to see answer by stanbon(75887)

Question 910693: a man has 3 pairs of shoes 8 pairs of socks, 4 pairs of slacks, and 9 sweaters. how many outfits can he wear?
Click here to see answer by Lenzky(18)

Question 910681: How many ways can 6 students be placed in 6 chairs
Click here to see answer by Lenzky(18)

Question 910620: How many ways can 5 positions be filled by 9 applicants?

Click here to see answer by Lenzky(18)

Question 909729: A certain company has 30 female employees including 3 in the management ranks and 150 male employees, including 12 in the management ranks. A committee consisting of 3 women and 3 men is to be chosen. How many ways are there to choose the committee if it has to include at least 1 person of management rank of each gender.
Click here to see answer by Lenzky(18)

Question 910780: How do you set up this question in order to solve it? You are building 16 digit passwords (numbers only). what is the probability that you create a password that has no repeated digits?
Click here to see answer by stanbon(75887)

Question 910808: Evaluate the following expression:
C(n,2)
I understand that it would be:
= n! / r!(n-r)!
= n! / 2!(n-2)!
I'm just not sure how to simplify this?
An explanation and answer would be really appreciated :)
Click here to see answer by ewatrrr(24785)

Question 910853: You write a piece of software that rand
Click here to see answer by richwmiller(17219)

Question 910851: You write a piece of software that randomly selects 5 customer names from a database and prints them
on the screen, one line per customer name, and then terminates. You test it on a small database that
contains 8 customers: 4 male and 4 female.
a) If a customer name can be selected at most once by a run of your program, what is the total
number of possible outcomes of a run of your program?
Click here to see answer by richwmiller(17219)

Question 910931: A doctor visits her patients during morning rounds. how many ways can the doctor visit 6 patients during the morning rounds.
Click here to see answer by josmiceli(19441)

Question 911099: a professor has five different tasks to assign, one to each of her five assistants. In how many different ways could she make the assignments
Click here to see answer by jim_thompson5910(35256)

Question 911098: how many different ways can a psychology student select five subjects from a pool of 20 subjects and assign each one to a different experiment
Click here to see answer by jim_thompson5910(35256)

Question 911138: In how many ways can 1 or more of the 20 students in a statistics class enter their classroom
Click here to see answer by richwmiller(17219)

Question 911172: There are seven man and five women in a line at a salsa dance club. the bouncer can't only let in two more men and two more women. how many ways can he choose from those in line? how many ways can he choose if instead he is told he can admit four people and at least two must be women?
Click here to see answer by ewatrrr(24785)

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