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Question 118735:
How many three-letter combinations can be made from the letters in the word BLACK?

Thanks I really need help with this!!!!
Click here to see answer by checkley71(8403)

Question 119877: Solve for n.
35. P(n,4) = 40[P(n-1,2)]

36. P(n,4) = 3[P(n,3)]

37. n[P(5,3)] = P(7,5)]

38. 208P(n,2) = P(16,4)

how exactly do you solve for n? please and thank you.

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Question 121408: a certain car averages 28 miles per gallon. gasoline cost 1.11 per gallon. to the number of miles the car would be expected to go on 250 worth of gasoline?

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Question 121929: "ringing the Changes" is a process where the bells in a tower are rung and all possible permutations. Westminster abbey has 10 bells in its tower. In how many ways can its bells be rung?
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Question 122357: how do i find the premutation on 13 p 8
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Question 122836: How many permutations of the leters ABCDEFG contain
(a)the string BCD
(b)the string CFGA
(c)the string BA & GF
(d)the string ABC & DE
(e)the string CBA & BED
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Question 125203: How many different numbers can be formed with the digits 2,4,6,8,0 each being divisible by ten, repetition of the digits being not allowed?
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Question 125202: How many numbers each less than 400 can be formed from the digits 1,2,3,4,5,6, if repetition is allowed?
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Question 125201: A,B& C be three towns. Suppose there are four routes between A & B. Ane five routes between B & C. In how many different ways one can travel from A to C via B?
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Question 125894: a shipment of 15 television sets contains four defective ones. in how many ways can one select 5 of these for inspection so that:
a. none of the defective television sets are included
b. both of the defective television sets are included
c. only one of the defective television sets are included
d. either two of the defective television sets or three of the non defective sets are included
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Question 128014: P(5,3)

I have tried 5!and added 3!
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Question 128817: Find the number of possible 5-card hands that contain the cards specified: 4 aces and 1 other card. I was able to find the formula for a 5-card hand with 2 aces but I'm lost. For 2 aces, it's C(52,5) - C(48,5) - C(4,1) X C(48,4) but I don't understand all the parts. I know C(52,5) is the total possiblilities of a 5-card hand out of 52 cards and C(48,5) is the 48 remaining cards but I'm not sure about the C(4,1) and the next C(48,4)?

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Question 129607: Given two six sided dice, compute the probability of rolling a nine.
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Question 130512: A seven digit phone number consists of a three-digit prefix followed by four digits. How many different phone numbers are possible for a particular prefix?
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Question 131198: A committee is going to select 5 students from a pool of 30 to receive scholarships. How many ways could the students be selected if each scholarship is a different amount?
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Question 131199: Consider eight points in a coordinate plane that no three are collinear. How many triangles can be drawn?
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Question 131197: In a round-robin tennis tournament, every player meets every other player exactly once. How many players can participate in a tournament of 45 matches?
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Question 132463: a booster club is saling meals at a basketball game a meal consist of a hamburger, personal pizza, chicken nuggets, sub sandwhich, chili, and tacos, the meals come with a drink that can include, tea, lemonade, cola, rootbeer, and kool aid
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Question 132491: how many different 4-digit numerals are there? (hint: zero cannot be used as the first digit)
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Question 132488: there are 3 roads connecting town A and B, and 4 roads connecting towns B and C. how many different routes are there from town A to town C?
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Question 134022: how many different six-digit numbers can be formed from the digits 1,2,3,4,5, and 6 if each digit is only used once?
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Question 134022: how many different six-digit numbers can be formed from the digits 1,2,3,4,5, and 6 if each digit is only used once?
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Question 134503: how many four-digit numbers starting with 1 and ending with 5 can be written if the digits 1 2 3 4 5 6 7 8 9 are used, including the cases when a digit may appear twice in a given number?
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Question 135425: why are the two types of circular permutations different?in case of beads (n-1)! is used and in case of beads (n-1)!/2 is used. why?? in case of flowers which one of them will be used??
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Question 136121: Evaluate

C
15 9
Answers to this question would be much obliged..the 15 is supposed to be on left side of the C,sorry.
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Question 136324: Hello. I appreciate all that you do here. This is my second time. I was very happy with how the answer was so in depth. Thank you very much. This one question has got me in the muddle at the moment. I have soem ideas. But a little lost. Here it is.
"Prove that if n is an Integer and log2 is Rational, then log2 n is an Integer?"

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Question 136380: how do you find the vertical and horizontal asymptotes, the hole and RD and graph the problem: y= 3/(x-2)(x+2)
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Question 136931: I have several word problems to solve but this is the first one. John owns a hotdog stand. His profit is represented by the equation P(x)=-x^2+12x+46, with P being profits and the x the number of hotdogs sold. What is the most he can earn?
Click here to see answer by dolly(163)

Question 136664: Jason is filling grab bags for the school festival. Two hundred
bags are lined up on a long table. He has already placed crackers and
other food items in each bag and now has a limited amount of prizes to
add to some of the bags. If he places prize A in every 8th bag, prize B in
every 12th bag, and prize C in every 15th bag, which bag will have all
three prizes?

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Question 137326: Divide using long division:
(12x squared - 35x + 8) divided by (4x - 1)
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Question 137450: i need to know the laest common multiple of the pair of polynomials and have them factored. i am stuck on these two:
1) (1)/6x2-11x+3 (+) (1)/8x2-18
2) 4r/r-2 (+) 4r/r+2

thank you for your help!
Click here to see answer by ankor@dixie-net.com(22740)

Question 139724: Can you please help me with this?
If one person is chosen randomly from the list of all the members of the House and Senate for that year, what is the probability that the person chosen was a Democratic senator?
Member of Democrat Republican Other Total
House 292 143 0 435
Senate 61 38 1 100
Total 353 181 1 535

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Question 139723: Please help me. We are working on probability and I am not so good with it. I am not sure it the answer would be 1/23--that just seems too easy. If you can please help me, I would be thankful. Here is the problem.
A bag contains 9 green marbles, 8 red marbles, and 7 blue marbles. Without looking, a marble is drawn from the bag. What is the probability that a red or a blue marble will be drawn?

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Question 139702: 8!
________
2!(8-2)!
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Question 139698: 4! x 6!
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Question 139740: I tried to do it myself. Can you please tell me if this is correct? If not, can you help me?
The 16 graduating seniors at a small high school are ranked according to their grade-point averages. Assuming there are no ties, what expression correctly shows the number of permutations of the seniors selected 5 at a time?
This is what I came up with.
P(16,5)=
16!
______
(16-5)!
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Question 139735: I tried to do this three times, but get lost in all the steps. Can you help me?
C(10,5)x C(15,8)
________________
C(12,11)
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Question 139704: C(10,5) x C(15,8)
__________________
C(12,11)
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Question 139703: P(8,5)
_____________
P(3,1)x P(5,4)
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Question 139869: What is the probability that a seven-digit phone number contains the number 7?
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Question 140691: How many ways could you hold 5 cards in your hand if 2 of the cards must be aces and the other 3 must be alike?
I have attempted and I get 4P2*(4P3*12) = 3456.
4P2 for the aces and 4P3*12 for the other three cards the 12 because there are twelve other sets of 4 alike cards to choose from. I am using permutations because order matters since it is asking about ways to hold them in your hand??? Is this right??
Click here to see answer by stanbon(75887)

Question 141747: when four dice are rolled simultaneously, in how many outcomes will at least one of the dice show 3? explain in detail
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Question 141937: Please help me solve this problem with a deck of cards, It has two parts.
You separate the 12 face cards out of a deck of 52 cards.
Assume that the remaining cards have been shuffle. Select 3 cards from the pile of face cards. Show how you derive the sulution. Tell if combination or permutation and why.
Part 1. How many ways are there of selecting one of each face card from the pile?
Part 2. How many ways are there of selecting 3 of the same face cards (ie, 3 jacks, 3 queens, 3 kings).
For part 1 my answer is 64 ways. combination, reason was not in any specific order.
for part 2, I said 12 ways, combination, reason not any speific order.
My teacher said I was wrong.
Can you show me every step. Please!!
Click here to see answer by stanbon(75887)

Question 142536: "To keep PC files secure, many programs require the user to enter a password. The shortest passwords must be at least 6 characters long and can contain both letters and digits." How many 6-character passwords are possible if characters can be repeated? Please explain HOW to find the answer. I am so stuck on this.
Click here to see answer by scott8148(6628)

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