हिंदी

A committee of 7 has to be formed from 9 boys and 4 girls. In how many ways can this be done when the committee consists of: atmost 3 girls?

Advertisements
Advertisements

प्रश्न

A committee of 7 has to be formed from 9 boys and 4 girls. In how many ways can this be done when the committee consists of: atmost 3 girls?

योग
Advertisements

उत्तर

If maximum 3 girls are to be included in the committee, then the committees will be formed as follows:

  1. No girls and 7 boys
  2. 1 girl and 6 boys
  3. 2 girls and 5 boys
  4. 3 girls and 4 boys

Hence, the total committees formed = 4C0 x 9C7 + 4C1 x 9C6 + 4C2 x 9C5 + 4C3 x 9C4

= 1 x 9C2 + 4C1 x 9C3 + 4C2 x 9C4 + 4C1 x 9C4

= 1 x `(9 xx 8)/(1 xx 2) + 4/1 xx (9 xx 8 xx 7)/(1 xx 2 xx 3) + (4 xx 3)/(1 xx 7) xx (9 xx 8 xx 7 xx 6)/(1 xx 2 xx 3 xx 4) + 4/1 xx (9 xx 8 xx 7 xx 6)/(1 xx 2 xx 3 xx 4)`

= 1 x 36 + 4 x 84 + 6 x 126 + 4 x 126

= 36 + 336 + 126 x (6+ 4)

= 372 + 1260

= 1632

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 6: Permutations and Combinations - Miscellaneous Exercise [पृष्ठ १२२]

APPEARS IN

एनसीईआरटी Mathematics [English] Class 11
अध्याय 6 Permutations and Combinations
Miscellaneous Exercise | Q 3. (iii) | पृष्ठ १२२
आर.डी. शर्मा Mathematics [English] Class 11
अध्याय 17 Combinations
Exercise 17.2 | Q 30.3 | पृष्ठ १७

वीडियो ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्न

How many words, with or without meaning, each of 2 vowels and 3 consonants can be formed from the letters of the word DAUGHTER?


Compute:

\[\frac{11! - 10!}{9!}\]

A coin is tossed five times and outcomes are recorded. How many possible outcomes are there?


How many three-digit numbers are there?


Since the  number has to be greater than 8000, the thousand's place can be filled by only two digits, i.e. 8 and 9.
Now, the hundred's place can be filled with the remaining 4 digits as the repetition of the digits is not allowed.
The ten's place can be filled with the remaining 3 digits.
The unit's place can be filled with the remaining 2 digits.
Total numbers that can be formed = `2xx4xx3xx2=48`


Evaluate the following:

14C3


If nC4 , nC5 and nC6 are in A.P., then find n.


If 16Cr = 16Cr + 2, find rC4.


How many different selections of 4 books can be made from 10 different books, if
there is no restriction;


How many different selections of 4 books can be made from 10 different books, if
two particular books are always selected;


From 4 officers and 8 jawans in how many ways can 6 be chosen. to include at least one officer?


In how many ways can a committee of 5 persons be formed out of 6 men and 4 women when at least one woman has to be necessarily selected?


A group consists of 4 girls and 7 boys. In how many ways can a team of 5 members be selected if the team has (i) no girl?


Determine the number of 5 cards combinations out of a deck of 52 cards if there is exactly one ace in each combination.


A bag contains 5 black and 6 red balls. Determine the number of ways in which 2 black and 3 red balls can be selected.


Out of 18 points in a plane, no three are in the same straight line except five points which are collinear. How many (ii) triangles can be formed by joining them?


If 20Cr = 20Cr + 4 , then rC3 is equal to


If nCr + nCr + 1 = n + 1Cx , then x =


There are 12 points in a plane. The number of the straight lines joining any two of them when 3 of them are collinear, is


If C0 + C1 + C2 + ... + Cn = 256, then 2nC2 is equal to


Given 11 points, of which 5 lie on one circle, other than these 5, no 4 lie on one circle. Then the number of circles that can be drawn so that each contains at least 3 of the given points is


How many different committees of 5 can be formed from 6 men and 4 women on which exact 3 men and 2 women serve?
(a) 6
(b) 20
(c) 60
(d) 120


The number of diagonals that can be drawn by joining the vertices of an octagon is


Find the value of 20C16 – 19C16 


In how many ways can the letters of the word 'IMAGE' be arranged so that the vowels should always occupy odd places?


A student has to answer 10 questions, choosing atleast 4 from each of Parts A and B. If there are 6 questions in Part A and 7 in Part B, in how many ways can the student choose 10 questions?


A boy has 3 library tickets and 8 books of his interest in the library. Of these 8, he does not want to borrow Mathematics Part II, unless Mathematics Part I is also borrowed. In how many ways can he choose the three books to be borrowed?


A bag contains 5 black and 6 red balls. Determine the number of ways in which 2 black and 3 red balls can be selected from the lot.


There are 10 lamps in a hall. Each one of them can be switched on independently. Find the number of ways in which the hall can be illuminated.


A group consists of 4 girls and 7 boys. In how many ways can a team of 5 members be selected if the team has at least one boy and one girl


If nC12 = nC8, then n is equal to ______.


The number of triangles that are formed by choosing the vertices from a set of 12 points, seven of which lie on the same line is ______.


There are 3 books on Mathematics, 4 on Physics and 5 on English. How many different collections can be made such that each collection consists of:

C1 C2
(a) One book of each subject; (i) 3968
(b) At least one book of each subject: (ii) 60
(c) At least one book of English: (iii) 3255

All possible numbers are formed using the digits 1, 1, 2, 2, 2, 2, 3, 4, 4 taken all at a time. The number of such numbers in which the odd digits occupy even places is ______.


Number of selections of at least one letter from the letters of MATHEMATICS, is ______.


There are 12 balls numbered from 1 to 12. The number of ways in which they can be used to fill 8 places in a row so that the balls are with numbers in ascending or descending order is equal to ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×