Advertisements
Advertisements
प्रश्न
Find the value of 15C4
उत्तर
15C4
= `(15!)/(4!(15 - 4)!) ...(∵ ""^"n""C"_"r" = ("n"!)/("r"!("n" - "r")!))`
= `(15!)/(4!11!)`
= `(15 xx 14 xx 13 xx 12 xx 11!)/(4 xx 3 xx 2 xx 1 xx 11!)`
= `(15xx14xx13xx12)/(4xx3xx2xx1)`
= 1365
APPEARS IN
संबंधित प्रश्न
Find n and r if `""^"n""C"_("r" - 1): ""^"n""C"_"r": ""^"n""C"_("r" + 1)` = 20:35:42
Find the number of diagonals of an n-shaded polygon. In particular, find the number of diagonals when: n = 15
Find x if `""^"n""P"_"r" = "x" ""^"n""C"_"r"`
Find the differences between the largest values in the following: `""^14"C"_r "and" ""^12"C"_r`
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 if nCn–3 = 84
Find the number of diagonals of an n-sided polygon. In particular, find the number of diagonals when n = 12
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
Ten points are plotted on a plane. Find the number of straight lines obtained by joining these points if no three points are collinear
Find r if 11C4 + 11C5 + 12C6 + 13C7 = 14Cr
Find the value of `sum_("r" = 1)^4 ""^((21 - "r"))"C"_4`
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 majority?
Five students are selected from 11. How many ways can these students be selected if two specified students are not selected?
Answer the following:
A student finds 7 books of his interest but can borrow only three books. He wants to borrow the Chemistry part-II book only if Chemistry Part-I can also be borrowed. Find the number of ways he can choose three books that he wants to borrow.
The maximum value of z = 9x + 11y subject to 3x + 2y ≤ 12, 2x + 3y ≤ 12, x ≥ 0, y ≥ 0 is _______.
In how many ways can a group of 5 boys and 6 girls be formed out of 10 boys and 11 girls?
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 ______.