Home
Class 12
MATHS
The total number of ways in which 2n per...

The total number of ways in which `2n` persons can be divided into `n` couples is a. `(2n !)/(n ! n !)` b. `(2n !)/((2!)^3)` c. `(2n !)/(n !(2!)^n)` d. none of these

A

`(2n!)/((n!)^(2))`

B

`(2n!)/((2n!)^(n))`

C

`(2n!)/(n!(2n!)^(2))`

D

None of these

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem of dividing `2n` persons into `n` couples, we can follow these steps: ### Step 1: Understand the problem We need to divide `2n` persons into `n` couples. Each couple consists of 2 persons. ### Step 2: Calculate the total arrangements of `2n` persons The total number of ways to arrange `2n` persons is given by `2n!`. ### Step 3: Account for the indistinguishability of couples Since each couple consists of 2 persons, the arrangement of each couple does not matter. Therefore, for each couple, we can arrange the 2 persons in `2!` ways. Since we have `n` couples, we need to divide by `(2!)^n` to account for the indistinguishable arrangements within each couple. ### Step 4: Account for the indistinguishability of the couples The `n` couples themselves can be arranged among themselves in `n!` ways. Since the order of the couples does not matter, we also need to divide by `n!`. ### Step 5: Combine the calculations Putting it all together, the total number of ways to divide `2n` persons into `n` couples is given by: \[ \text{Total ways} = \frac{2n!}{n! \cdot (2!)^n} \] ### Conclusion Thus, the correct answer is option (c): \(\frac{2n!}{n!(2!)^n}\). ---
Promotional Banner

Topper's Solved these Questions

  • PERMUTATIONS AND COMBINATIONS

    ARIHANT MATHS ENGLISH|Exercise Exercise For Session 6|26 Videos
  • PERMUTATIONS AND COMBINATIONS

    ARIHANT MATHS ENGLISH|Exercise Exercise For Session 7|5 Videos
  • PERMUTATIONS AND COMBINATIONS

    ARIHANT MATHS ENGLISH|Exercise Exercise For Session 4|18 Videos
  • PARABOLA

    ARIHANT MATHS ENGLISH|Exercise Exercise (Questions Asked In Previous 13 Years Exam)|36 Videos
  • PROBABILITY

    ARIHANT MATHS ENGLISH|Exercise Exercise (Questions Asked In Previous 13 Years Exam)|54 Videos

Similar Questions

Explore conceptually related problems

Number of ways in which three numbers in A.P. can be selected from 1,2,3,..., n is a. ((n-1)/2)^2 if n is even b. n(n-2)/4 if n is even c. (n-1)^2/4 if n is odd d. none of these

If x^m occurs in the expansion (x+1//x^2)^(2n) , then the coefficient of x^m is a. ((2n)!)/((m)!(2n-m)!) b. ((2n)!3!3!)/((2n-m)!) c. ((2n)!)/(((2n-m)/3)!((4n+m)/3)!) d. none of these

Number of sub parts into which ‘n’ straight lines in a plane can divide it is: (a) (n^(2)+n+2)/(2) (b) (n^(2)+n+4)/(2) (c) (n^(2)+n+6)/(2) (d) none

The coefficient of 1//x in the expansion of (1+x)^n(1+1//x)^n is (n !)/((n-1)!(n+1)!) b. ((2n)!)/((n-1)!(n+1)!) c. ((2n)!)/((2n-1)!(2n+1)!) d. none of these

The coefficient of 1//x in the expansion of (1+x)^n(1+1//x)^n is (a). (n !)/((n-1)!(n+1)!) (b). ((2n)!)/((n-1)!(n+1)!) (c). ((2n)!)/((2n-1)!(2n+1)!) (d). none of these

Two players P_1a n dP_2 play a series of 2n games. Each game can result in either a win or a loss for P_1dot the total number of ways in which P_1 can win the series of these games is equal to a. 1/2(2^(2n)-^ "^(2n)C_n) b. 1/2(2^(2n)-2xx^"^(2n)C_n) c. 1/2(2^n-^"^(2n)C_n) d. 1/2(2^n-2xx^"^(2n)C_n)

In a n- sided regular polygon, the probability that the two diagonal chosen at random will intersect inside the polygon is: (a.) (2^n C_2)/(^(^(n C_(2-n)))C_2) (b.) ("^(n(n-1))C_2)/(^(^(n C_(2-n)))C_2) (c.) (^n C_4)/(^(^(n C_2-n))C_2) (d.) none of these

In a n- sided regular polygon, the probability that the two diagonal chosen at random will intersect inside the polygon is (2^n C_2)/(^(^(n C_(2-n)))C_2) b. (^(n(n-1))C_2)/(^(^(n C_(2-n)))C_2) c. (^n C_4)/(^(^(n C_(2-n)))C_2) d. none of these

The total number of ways in which n^2 number of identical balls can be put in n numbered boxes (1,2,3,.......... n) such that ith box contains at least i number of balls is a. .^(n^2)C_(n-1) b. .^(n^2-1)C_(n-1) c. .^((n^2+n-2)/2)C_(n-1) d. none of these

The total number of terms which are dependent on the value of x in the expansion of (x^2-2+1/(x^2))^n is equal to 2n+1 b. 2n c. n d. n+1

ARIHANT MATHS ENGLISH-PERMUTATIONS AND COMBINATIONS -Exercise For Session 5
  1. There are 3 oranges, 5 apples and 6 mangoes in a fuit basket (all frui...

    Text Solution

    |

  2. In a city no two persons have identical set of teeth and there is no p...

    Text Solution

    |

  3. If a1,a2,a3,.....,a(n+1) be (n+1) different prime numbers, then the n...

    Text Solution

    |

  4. Number of proper factors of 2400 is equal to (a) 34 (b) 35 (c) 36 (d...

    Text Solution

    |

  5. The sum of the divisors of 2^(5)xx3^(4)xx5^(2), is

    Text Solution

    |

  6. The number of proper divisors of 2^(p)*6^(q)*21^(r),AA p,q,r in N, is

    Text Solution

    |

  7. The number of odd proper divisors of 3^(p)*6^(q)*15^(r),AA p,q,r, in N...

    Text Solution

    |

  8. The number of proper divisors of 1800, which are also divisible by 10,...

    Text Solution

    |

  9. Total number of 480 that are of the form 4n+2, n ge 0, is equal to

    Text Solution

    |

  10. Total number of divisors of N=2^(5)*3^(4)*5^(10)*7^(6) that are of the...

    Text Solution

    |

  11. Total number of divisors of n = 3^5. 5^7. 7^9 that are in the form of ...

    Text Solution

    |

  12. In how many ways 12 different books can be distributed equally among 3...

    Text Solution

    |

  13. Number of ways in which 12 different things can be distributed in 3 gr...

    Text Solution

    |

  14. Number of ways in which 12 different things can be divided among five ...

    Text Solution

    |

  15. Number of ways in which 12 different things can be divided among five ...

    Text Solution

    |

  16. The total number of ways in which 2n persons can be divided into n ...

    Text Solution

    |

  17. n different toys have to be distributed among n children. Find the num...

    Text Solution

    |

  18. In how any ways can 8 different books be distributed among 3 students ...

    Text Solution

    |