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Recent questions in Combinatory
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Combinatorics:
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1
Kenneth Rosen chapter 5 20 discrete mathematics
A playoff between two teams consists of at most five games . The first team that wins three games wins the playoff. In how many different way playoff occur?
[closed]
asked
3 days
ago
in
Combinatory
by
Ram Swaroop
Active
(
2.2k
points)

21
views
kennethrosen
discretemathematics
permutationsandcombinations
0
votes
1
answer
2
Self Doubt
From a group of 5 woman and 7 man we have to select a committee consisting of 2 woman and 3 men. Find the total number of ways to select such committed if (1 and 2 are a separate question) 1. Four man refuse to be in the same committee 2. 2 woman refuse to be in the same committee.
asked
Feb 8
in
Combinatory
by
smsubham
Loyal
(
9.1k
points)

49
views
counting
permutationsandcombinations
discretemathematic
discretemathematics
+1
vote
1
answer
3
GATE20195
Let $U = \{1, 2, \dots , n\}$ Let $A=\{(x, X) \mid x \in X, X \subseteq U \}$. Consider the following two statements on $\mid A \mid$. $\mid A \mid = n2^{n1}$ $\mid A \mid = \Sigma_{k=1}^n k \begin{pmatrix} n \\ k \end{pmatrix}$ Which of the above statements is/are TRUE? Only I Only II Both I and II Neither I nor II
asked
Feb 7
in
Combinatory
by
Arjun
Veteran
(
384k
points)

1.9k
views
gate2019
engineeringmathematics
discretemathematics
permutationsandcombinations
+1
vote
1
answer
4
Letters in boxes  combinations
Q .) The number of ways can 5 letter be put in 3 boxes A, B,C such that A has at least 2 letters. My approach: Number of ways to choose 2 letters out of 5 is 5C2. And for each such combination the remaining 3 letter have 3 choice. Therefore 5C2 * 3^3, but this is incorrect. Please point out the fault in my understanding and also the correct way to solve it
asked
Jan 31
in
Combinatory
by
shaz
(
347
points)

40
views
permutationsandcombinations
0
votes
0
answers
5
Arrangement
Number of ways we can arrange 5 books in 3 selves___________
[closed]
asked
Jan 31
in
Combinatory
by
srestha
Veteran
(
108k
points)

72
views
permutationsandcombinations
0
votes
0
answers
6
test series question
the no. of ways we can arrange 5 books in 3 shelves?
[closed]
asked
Jan 30
in
Combinatory
by
Ashwani Yadav
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1.1k
points)

56
views
madeeasytestseries
0
votes
0
answers
7
The number of ways in which we can place 3 white pawns and 3 black pawns on a 3 . 3 Chessboard is equal to
[closed]
asked
Jan 30
in
Combinatory
by
mehul vaidya
Active
(
3k
points)

23
views
0
votes
0
answers
8
Arrangement Problem
The number of ways, we can arrange 5 books in 3 shelves ________. Given answer 2520 n=3 r=5 so answer is 31+5 P5= 7p5= 2520 My answer 3*3*3*3*3= 243 Where am I doing wrong? please help
[closed]
asked
Jan 29
in
Combinatory
by
Mayank Bansal
(
73
points)

40
views
permutationsandcombinations
0
votes
2
answers
9
MadeEasy Test Series
What is the number of seven digit integers possible with sum of the digits equal to 11 and formed by using the digits 1, 2 and 3 only?
asked
Jan 29
in
Combinatory
by
mehul vaidya
Active
(
3k
points)

78
views
0
votes
1
answer
10
Ace pregate
Let S={a,b,c,d,e}. Number of strings of length 5 possible with the letters of S , so that atleast two A's are consecutive is? Answer given is : 421
asked
Jan 27
in
Combinatory
by
Vignaneswarkrishna
(
167
points)

37
views
0
votes
0
answers
11
#Combinatorics
asked
Jan 24
in
Combinatory
by
vipul2097
(
43
points)

69
views
0
votes
0
answers
12
ace test series question on number of palindromes
asked
Jan 24
in
Combinatory
by
Shankar Kakde
(
369
points)

26
views
0
votes
0
answers
13
ME ADVANCE TEST
The number of ways in which we can place 3 white pawns and 3 black pawns on a 3 × 3 Chessboard is equal to
asked
Jan 23
in
Combinatory
by
himgta
Active
(
3.6k
points)

50
views
0
votes
0
answers
14
made easy test
The number of ways 5 letter be put in 3 letter boxes A,B,C. If letter box A must contain at least 2 letters.
asked
Jan 22
in
Combinatory
by
snaily16
(
255
points)

120
views
madeeasytestseries
permutationsandcombinations
discretemathematics
+1
vote
0
answers
15
Made easy test series
in how many ways 6 letters can be placed in 6 envelopes such that at least 4 letters go into their corresponding envelopes ?
asked
Jan 19
in
Combinatory
by
ronin_codex
(
19
points)

129
views
madeeasytestseries
discretemathematics
permutationsandcombinations
combinatory
0
votes
1
answer
16
nptel
Q.1 In a country there are coins of denominations $2, $3, $5 and $7. How many different ways are there to pay exactly $10? approach??
asked
Jan 19
in
Combinatory
by
BASANT KUMAR
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(
2.4k
points)

25
views
+1
vote
0
answers
17
made easy adv mock
the number of ways in which we can place 3 white pawns and 3 black pawns on a 3*3 chessboard my answer was 12. approach : we cant have any 2 black pawns or 2 white pawns in the same row or column {3*2*1} * {2*1 * 1} am i correct??
asked
Jan 18
in
Combinatory
by
Gate Fever
Active
(
4.7k
points)

90
views
0
votes
0
answers
18
************ Test series
Consider the graph G whose vertices are 4 element subsets of the set {1, 2, 3…10} with two vertices adjacent if and only if their intersection is empty. Then the number of edges does G have
asked
Jan 17
in
Combinatory
by
M.G
(
445
points)

32
views
0
votes
0
answers
19
Test series
In how many ways 20 two rupees coins can be distributed among 4 children? Answer – 1771
asked
Jan 16
in
Combinatory
by
sahil_malik
(
373
points)

64
views
0
votes
0
answers
20
How to solve this question
If seven colors are used to paint 50 bicycles then which of the following statements need not be true? at least eight bicycles are of the same color at least seven bicycles are of the same color at least nine bicycles are of the same color at most eight bicycles are of the same color
asked
Jan 16
in
Combinatory
by
`JEET
Active
(
3.3k
points)

51
views
pigeonholeprinciple
0
votes
1
answer
21
How to solve such question
The number of ways can 10 balls be chosen from an urn containing 10 identical green balls, 5 identical yellow balls and 3 identical blue balls are _______________.
asked
Jan 16
in
Combinatory
by
`JEET
Active
(
3.3k
points)

19
views
0
votes
1
answer
22
generating function
asked
Jan 15
in
Combinatory
by
Rahul_Rathod_
Junior
(
565
points)

72
views
generatingfunctions
discretemathematics
permutationsandcombinations
#discrete
0
votes
1
answer
23
#combinatorics
How many ways the letters of the word “AABCCD” can be arranged such that, these neither begin with ‘A’ nor end with D ?
asked
Jan 15
in
Combinatory
by
Satbir
Active
(
4.9k
points)

62
views
permutationsandcombinations
engineeringmathematics
0
votes
0
answers
24
MADE EASY TEST SERIES
Let We define Then ar is equal to. $\binom{r}{2019}$ $\binom{r}{r + 2018}$ $\binom{r}{2019 – r}$ $\binom{r}{r – 2018}$ Can anyone tell me if this type of question is in Gate 2019 syllabus or not because I have never seen such question in previous year question? If yes, then when can I learn this stuff from. Because I am unable to understand the whole solution.
asked
Jan 13
in
Combinatory
by
jhaanuj2108
(
215
points)

35
views
madeeasytestseries
discretemathematics
coefficient
0
votes
0
answers
25
made easy
let an be the recurrenence relation which satisfies $a_{n}=4(a_{n1}a_{n2})$ with $a_{1}$=2 and $a_{2}=8$. let X corresponds to the value of $a_{17}$.then values of $log_{2}(\left  x \right )$ will be _____? am getting 18.
[closed]
asked
Jan 11
in
Combinatory
by
Gate Fever
Active
(
4.7k
points)

55
views
0
votes
0
answers
26
APPLIEDCOURSEMOCKTEST2
How many 5 digit numbers can be formed if either (a) every successive digit exceeds its predecessor ,or (b) every successive digit is smaller than it’s predecessor Note:leading 0’s don’t count ,like 04521 is not a 5digit number._
asked
Jan 9
in
Combinatory
by
Prateek Raghuvanshi
Loyal
(
9.6k
points)

51
views
0
votes
0
answers
27
APPLIEDCOURSEmocktest2
for whole number n, consider the following recurrence relation defined as $a_{n+2}=(n+3)a_{n+1}(n+2)a_n$ and $a_1=1,a_2=3$ find $( \sum_{k=1}^{2015}a_k)(mod\; 100)$ is _
asked
Jan 9
in
Combinatory
by
Prateek Raghuvanshi
Loyal
(
9.6k
points)

38
views
numericalanswers
0
votes
0
answers
28
Finding the coefficient
What is its answer ?
asked
Jan 9
in
Combinatory
by
Nandkishor3939
Active
(
1.2k
points)

20
views
engineeringmathematics
permutationsandcombinations
discretemathematics
0
votes
0
answers
29
ACE ACADEMY
asked
Jan 6
in
Combinatory
by
Sinchit
(
39
points)

24
views
acetestseries
0
votes
1
answer
30
[MEasy Test Discrete]
The number of seven digit integers possible with sum of the digits equal to 11 and formed by using the digits 1, 2 and 3 only are ________.
asked
Jan 5
in
Combinatory
by
VikramRB
(
205
points)

52
views
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