Advertisements
Advertisements
प्रश्न
Five students are selected from 11. How many ways can these students be selected if two specified students are not selected?
उत्तर
Number of students is 11. We have to select 5 students
2 particular students are not selected:
If 2 particular students are not selected, then from remaining (11 – 2) = 9 students, we have to select 5 students.
This can be done in 9C5 ways.
∴ total number of selections
= 9C5
= `9/(5!4!)`
= `(9 xx 8 xx 7 xx 6)/(1 xx 2 xx 3 xx 4)`
= 126.
APPEARS IN
संबंधित प्रश्न
Find the value of `""^80"C"_2`
Find the value of `""^15"C"_4 + ""^15"C"_5`
Find the value of `""^20"C"_16 - ""^19"C"_16`
If `""^"n""P"_"r" = 1814400` and `""^"n""C"_"r"` = 45, find r.
If `""^"n""C"_("r" - 1)` = 6435, `""^"n""C"_"r"` = 5005, `""^"n""C"_("r" + 1)` = 3003, find `""^"r""C"_5`.
Find the number of ways of selecting a team of 3 boys and 2 girls from 6 boys and 4 girls.
Find the number of diagonals of an n-shaded polygon. In particular, find the number of diagonals when: n = 10
Ten points are plotted on a plane. Find the number of straight lines obtained by joining these points if four points are collinear.
A word has 8 consonants and 3 vowels. How many distinct words can be formed if 4 consonants and 12 vowels are chosen?
Find n, if `""^23"C"_(3"n") = ""^23"C"_(2"n" + 3)`
Find n, if `""^"n""C"_("n" - 2)` = 15
Find the differences between the largest values in the following: `""^14"C"_r "and" ""^12"C"_r`
Find the differences between the largest values in the following: `""^15"C"_r "and" ""^11"C"_r`
A group consists of 9 men and 6 women. A team of 6 is to be selected. How many of possible selections will have at least 3 women?
A committee of 10 persons is to be formed from a group of 10 women and 8 men. How many possible committees will have at least 5 women? How many possible committees will have men in the majority?
Find n and r if nPr = 720 and nCn–r = 120
Find n and r if nCr–1 : nCr : nCr+1 = 20 : 35 : 42
Find the number of ways of drawing 9 balls from a bag that has 6 red balls, 8 green balls, and 7 blue balls so that 3 balls of every colour are drawn
Find the number of ways of selecting a team of 3 boys and 2 girls from 6 boys and 4 girls
Find the number of diagonals of an n-sided polygon. In particular, find the number of diagonals when n = 10
Find the number of diagonals of an n-sided polygon. In particular, find the number of diagonals when n = 15
Find the number of diagonals of an n-sided polygon. In particular, find the number of diagonals when n = 8
There are 20 straight lines in a plane so that no two lines are parallel and no three lines are concurrent. Determine the number of points of intersection
Find the number of triangles formed by joining 12 points if four points are collinear
Find the differences between the greatest values in the following:
13Cr and 8Cr
In how many ways can a boy invite his 5 friends to a party so that at least three join the party?
A group consists of 9 men and 6 women. A team of 6 is to be selected. How many of possible selections will have at least 3 women?
Five students are selected from 11. How many ways can these students be selected if two specified students are selected?
Select the correct answer from the given alternatives.
A question paper has two parts, A and B, each containing 10 questions. If a student has to choose 8 from part A and 5 from part B, In how many ways can he choose the questions?
Select the correct answer from the given alternatives.
The number of arrangements of the letters of the word BANANA in which two N's do not appear adjacently
Answer the following:
There are 4 doctors and 8 lawyers in a panel. Find the number of ways for selecting a team of 6 if at least one doctor must be in the team
The maximum value of z = 9x + 11y subject to 3x + 2y ≤ 12, 2x + 3y ≤ 12, x ≥ 0, y ≥ 0 is _______.
If vertices of a parallelogram are respectively (2, 2), (3, 2), (4, 4), and (3, 4), then the angle between diagonals is ______
If 'n' is positive integer and three consecutive coefficient in the expansion of (1 + x)n are in the ratio 6 : 33 : 110, then n is equal to ______.
Out of 7 consonants and 4 vowels, the number of words (not necessarily meaningful) that can be made, each consisting of 3 consonants and 2 vowels, is ______.
