Advertisements
Advertisements
प्रश्न
Suppose m men and n women are to be seated in a row so that no two women sit together. If m > n, show that the number of ways in which they can be seated is `(m!(m + 1)!)/((m - n + 1)1)`
उत्तर
Let the men take their seats first.
They can be seated in mPm ways as shown in the following figure
From the above figure, we observe, that there are (m + 1) places for n women.
It is given that m > n and no two women can sit together.
Therefore, n women can take their seats (m+1)Pn ways
And hence the total number of ways so that no two women sit together is
`(""^nP_m) xx (""^(m + 1)P_n) = (m!(m + 1)!)/((m - n + 1)1)`
APPEARS IN
संबंधित प्रश्न
Evaluate 8!
Compute `(8!)/(6! xx 2!)`
Evaluate `(n!)/((n-r)!)`, when n = 9, r = 5
If three six faced die each marked with numbers 1 to 6 on six faces, are thrown find the total number of possible outcomes ?
How many natural numbers less than 1000 can be formed from the digits 0, 1, 2, 3, 4, 5 when a digit may be repeated any number of times?
Find the total number of ways in which 20 balls can be put into 5 boxes so that first box contains just one ball ?
In how many ways can 4 prizes be distributed among 5 students, when
(i) no student gets more than one prize?
(ii) a student may get any number of prizes?
(iii) no student gets all the prizes?
Evaluate each of the following:
Write the number of ways in which 7 men and 7 women can sit on a round table such that no two women sit together ?
Write the number of all possible words that can be formed using the letters of the word 'MATHEMATICS'.
Write the number of ways in which 6 men and 5 women can dine at a round table if no two women sit together ?
The number of permutations of n different things taking r at a time when 3 particular things are to be included is
The number of ways in which the letters of the word 'CONSTANT' can be arranged without changing the relative positions of the vowels and consonants is
Number of all four digit numbers having different digits formed of the digits 1, 2, 3, 4 and 5 and divisible by 4 is
If the letters of the word KRISNA are arranged in all possible ways and these words are written out as in a dictionary, then the rank of the word KRISNA is
A 5-digit number divisible by 3 is to be formed using the digits 0, 1, 2, 3, 4 and 5 without repetition. The total number of ways in which this can be done is
The number of arrangements of the letters of the word BHARAT taking 3 at a time is
Find the number of arrangements that can be made out of the letters of the word “ASSASSINATION”.
Evaluate the following.
`(3! xx 0! + 0!)/(2!)`
The total number of 9 digit number which has all different digit is:
Suppose 8 people enter an event in a swimming meet. In how many ways could the gold, silver and bronze prizes be awarded?
A test consists of 10 multiple choice questions. In how many ways can the test be answered if each question has four choices?
How many strings can be formed from the letters of the word ARTICLE, so that vowels occupy the even places?
A coin is tossed 8 times, how many different sequences of heads and tails are possible?
If the letters of the word GARDEN are permuted in all possible ways and the strings thus formed are arranged in the dictionary order, then find the ranks of the words
DANGER
Choose the correct alternative:
If Pr stands for rPr then the sum of the series 1 + P1 + 2P2 + 3P3 + · · · + nPn is
In how many ways can 5 children be arranged in a line such that two particular children of them are always together
A five-digit number divisible by 3 is to be formed using the numbers 0, 1, 2, 3, 4 and 5 without repetitions. The total number of ways this can be done is ______.