English

How Many Words Can Be Formed with the Letters of the Word 'Parallel' So that All L'S Do Not Come Together?

Advertisements
Advertisements

Question

How many words can be formed with the letters of the word 'PARALLEL' so that all L's do not come together?

Advertisements

Solution

The word PARALLEL consists of 8 letters that include two As and three Ls.
Total number of words that can be formed using the letters of the word PARALLEL =\[\frac{8!}{2!3!}\] = 3360

Number of words in which all the Ls come together is equal to the condition if all three Ls are considered as a single entity.
So, we are left with total 6 letters that can be arranged in\[\frac{6!}{2!}\] ways (divided by 2! since there are two As), which is equal to 360.Number of words in which all Ls do not come together = Total number of words\[-\] Number of words in which all the Ls come together =  3360\[-\]360= 3000

shaalaa.com
Factorial N (N!) Permutations and Combinations
  Is there an error in this question or solution?
Chapter 16: Permutations - Exercise 16.5 [Page 43]

APPEARS IN

R.D. Sharma Mathematics [English] Class 11
Chapter 16 Permutations
Exercise 16.5 | Q 5 | Page 43

RELATED QUESTIONS

Convert the following products into factorials:

1 · 3 · 5 · 7 · 9 ... (2n − 1)


Prove that:

\[\frac{n!}{(n - r)! r!} + \frac{n!}{(n - r + 1)! (r - 1)!} = \frac{(n + 1)!}{r! (n - r + 1)!}\]


If nP4 = 360, find the value of n.


If P (n − 1, 3) : P (n, 4) = 1 : 9, find n.


If P (n, 5) : P (n, 3) = 2 : 1, find n.


Prove that:1 . P (1, 1) + 2 . P (2, 2) + 3 . P (3, 3) + ... + n . P (nn) = P (n + 1, n + 1) − 1.


In how many ways can five children stand in a queue?


From among the 36 teachers in a school, one principal and one vice-principal are to be appointed. In how many ways can this be done?


Four letters E, K, S and V, one in each, were purchased from a plastic warehouse. How many ordered pairs of letters, to be used as initials, can be formed from them?


Find the number of different 4-letter words, with or without meanings, that can be formed from the letters of the word 'NUMBER'.


There are 6 items in column A and 6 items in column B. A student is asked to match each item in column A with an item in column B. How many possible, correct or incorrect, answers are there to this question?


In how many ways can 6 boys and 5 girls be arranged for a group photograph if the girls are to sit on chairs in a row and the boys are to stand in a row behind them?


If a denotes the number of permutations of (x + 2) things taken all at a time, b the number of permutations of x things taken 11 at a time and c the number of  permutations of x − 11 things taken all at a time such that a = 182 bc, find the value of x.


All the letters of the word 'EAMCOT' are arranged in different possible ways. Find the number of arrangements in which no two vowels are adjacent to each other.


How many different words can be formed from the letters of the word 'GANESHPURI'? In how many of these words:

the vowels are always together?


How many permutations can be formed by the letters of the word, 'VOWELS', when
each word begins with E?


How many permutations can be formed by the letters of the word, 'VOWELS', when

each word begins with O and ends with L?


How many permutations can be formed by the letters of the word, 'VOWELS', when

all vowels come together?


How many words can be formed out of the letters of the word 'ARTICLE', so that vowels occupy even places?


How many words (with or without dictionary meaning) can be made from the letters in the word MONDAY, assuming that no letter is repeated, if all letters are used at a time.


Find the number of words formed by permuting all the letters of the following words:

PAKISTAN


Find the number of words formed by permuting all the letters of the following words:
SERIES


Find the number of words formed by permuting all the letters of the following words:
CONSTANTINOPLE


Find the total number of arrangements of the letters in the expression a3 b2 c4 when written at full length.


How many numbers can be formed with the digits 1, 2, 3, 4, 3, 2, 1 so that the odd digits always occupy the odd places?


How many different signals can be made from 4 red, 2 white and 3 green flags by arranging all of them vertically on a flagstaff?


How many permutations of the letters of the word 'MADHUBANI' do not begin with M but end with I?


Find the number of numbers, greater than a million, that can be formed with the digits 2, 3, 0, 3, 4, 2, 3.


Prove that: 4nC2n : 2nCn = [1 · 3 · 5 ... (4n − 1)] : [1 · 3 · 5 ... (2n − 1)]2.


Evaluate

\[^ {20}{}{C}_5 + \sum^5_{r = 2} {}^{25 - r} C_4\]

Let r and n be positive integers such that 1 ≤ r ≤ n. Then prove the following:

\[\frac{^{n}{}{C}_r}{^{n - 1}{}{C}_{r - 1}} = \frac{n}{r}\]

How many words, with or without meaning can be formed from the letters of the word 'MONDAY', assuming that no letter is repeated, if  all letters are used at a time 


If 35Cn +7 = 35C4n − 2 , then write the values of n.


Write the maximum number of points of intersection of 8 straight lines in a plane.


Write the number of parallelograms that can be formed from a set of four parallel lines intersecting another set of three parallel lines.


Write the total number of words formed by 2 vowels and 3 consonants taken from 4 vowels and 5 consonants.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×