Question

Max number of unique combinations

score 310 · Answer 1 · 2019-05-04 02:54:41

310

Views

Max number of unique combinations

Published on 04 May 2019 - 2:54

score 12.3k · Answer 2 · 2019-05-04 07:48:40

12.3k

Views

A coin is tossed $5$ times. How many possible outcomes contain AT MOST $3$ heads

Published on 04 May 2019 - 7:48

score 783 · Answer 3 · 2019-05-04 11:54:13

783

Views

The number of positive integers of 5 digits such that each digit is 1, 2 or 3, and all three of the digits appear atleast once.

Published on 04 May 2019 - 11:54

score 45 · Answer 4 · 2019-05-04 13:21:08

45

Views

Combination Summation problem

Published on 04 May 2019 - 13:21

score 1.4k · Answer 5 · 2019-05-05 01:42:14

1.4k

Views

In how many ways can the letters of the following word taken two at a time, be selected?

Published on 05 May 2019 - 1:42

score 152 · Answer 6 · 2019-05-05 06:56:10

152

Views

What is the probability that when a dice is rolled $6$ times, the sum of scores is $20$?

Published on 05 May 2019 - 6:56

score 34 · Answer 7 · 2026-03-25 09:29:51

34

Views

$\sum_{0\leqslant y \leqslant z \leqslant k \leqslant n} (\binom{n}{k}\binom{n-k}{z}\binom{n-k-z}{y})$ =?

Published on 25 Mar 2026 - 9:29

score 46 · Answer 8 · 2019-05-05 15:24:48

46

Views

Inviting your friend.

Published on 05 May 2019 - 15:24

score 165 · Answer 9 · 2019-05-06 18:24:56

165

Views

Prove by double-counting: $\sum_{k=d} ^n {n \choose k} {k \choose d} = 2^ {(n-d)} {n \choose d} $?

Published on 06 May 2019 - 18:24

score 110 · Answer 10 · 2019-05-06 21:48:46

110

Views

A form has 7 questions, each with 3 possible answers: A , B , or C. How many ways that the answer sheet has the same number of A and B

Published on 06 May 2019 - 21:48

score 336 · Answer 11 · 2019-05-07 00:39:07

336

Views

Prove $\sum_ {k=0} ^n {n \choose k}^2 = {2n \choose n} $?

Published on 07 May 2019 - 0:39

score 1.1k · Answer 12 · 2019-05-07 02:20:39

1.1k

Views

how many ways can 5 prizes be given to a group of 20 people with restrictions

Published on 07 May 2019 - 2:20

score 54 · Answer 13 · 2019-05-07 11:56:45

54

Views

Chance of spotting an incorrect value by random checks in a string

Published on 07 May 2019 - 11:56

score 250 · Answer 14 · 2026-03-26 20:25:47

250

Views

Find the largest integer $k$ for which $3^k$ divides $400 \choose 200$.

Published on 26 Mar 2026 - 20:25

score 272 · Answer 15 · 2019-05-07 18:06:32

272

Views

Why is $n^{\pi (2)− \pi ()} ≤ {2 \choose }$?

Published on 07 May 2019 - 18:06

List Question

Max number of unique combinations

A coin is tossed $5$ times. How many possible outcomes contain AT MOST $3$ heads

The number of positive integers of 5 digits such that each digit is 1, 2 or 3, and all three of the digits appear atleast once.

Combination Summation problem

In how many ways can the letters of the following word taken two at a time, be selected?

What is the probability that when a dice is rolled $6$ times, the sum of scores is $20$?

$\sum_{0\leqslant y \leqslant z \leqslant k \leqslant n} (\binom{n}{k}\binom{n-k}{z}\binom{n-k-z}{y})$ =?

Inviting your friend.

Prove by double-counting: $\sum_{k=d} ^n {n \choose k} {k \choose d} = 2^ {(n-d)} {n \choose d} $?

A form has 7 questions, each with 3 possible answers: A , B , or C. How many ways that the answer sheet has the same number of A and B

Prove $\sum_ {k=0} ^n {n \choose k}^2 = {2n \choose n} $?

how many ways can 5 prizes be given to a group of 20 people with restrictions

Chance of spotting an incorrect value by random checks in a string

Find the largest integer $k$ for which $3^k$ divides $400 \choose 200$.

Why is $n^{\pi (2)− \pi ()} ≤ {2 \choose }$?

Trending Questions

Popular # Hahtags

Popular Questions