Ask Questions, Get Answers
Menu
X
JEEMAIN Crash Practice
15 Test Series
NEET Crash Practice
15 Test Series
CBSE XII
Math
JEEMAIN
Math
Physics
Chemistry
Practice Test Series
CBSE XI
Math
NEET
Physics
Chemistry
Biology - XII
Biology - XI
Olympiad class V
Math - 5 Test Series
Olympiad class VI
Math - 5 Test Series
studyplans
JEEMAIN Crash Practice
15 Test Series
NEET Crash Practice
15 Test Series
CBSE XII
Math
JEEMAIN
Math
Physics
Chemistry
Practice Test Series
CBSE XI
Math
NEET
Physics
Chemistry
Biology - XII
Biology - XI
Olympiad class V
Math - 5 Test Series
Olympiad class VI
Math - 5 Test Series
mobile
exams
ask
sample papers
tutors
pricing
login
X
ASK
Home
>>
CBSE XI
>>
Math
>>
Permutations and Combinations
$15C_8+15C_9-15C_6-15C_7$=_____
$\begin{array}{1 1}(A)\;0\\(B)\;1\\(C)\;2\\(D)\;3\end{array} $
cbse
math
class11
ch7
permutations-and-combinations
exercise7-3
exemplar
q42
sec-a
easy
Share
asked
May 16, 2014
by
sreemathi.v
edited
May 16, 2014
Please
log in
or
register
to add a comment.
Please
log in
or
register
to answer this question.
1 Answer
Toolbox:
$nC_r=\large\frac{n!}{r!(n-r)!}$
$nC_r+nC_{r+1}-nC_r-nC_{r+1}$
$\Rightarrow 0$
Hence (A) is the correct answer.
answered
May 16, 2014
by
sreemathi.v
Please
log in
or
register
to add a comment.
Related questions
Using the digits 1,2,3,4,5,6,7,a number of 4 different digit is formed.Find (d) How many of these are exactly divisible by 4
cbse
math
class11
ch7
permutations-and-combinations
exercise7-3
exemplar
q63-d
sec-a
easy
asked
May 19, 2014
by
sreemathi.v
1
answer
Using the digits 1,2,3,4,5,6,7,a number of 4 different digit is formed.Find (c) How many numbers are exactly divisible by 25
cbse
math
class11
ch7
permutations-and-combinations
exercise7-3
exemplar
q63-c
sec-a
easy
asked
May 19, 2014
by
sreemathi.v
1
answer
Using the digits 1,2,3,4,5,6,7,a number of 4 different digit is formed.Find (a) How many numbers are formed
cbse
math
class11
ch7
permutations-and-combinations
exercise7-3
exemplar
q63-a
sec-a
easy
asked
May 19, 2014
by
sreemathi.v
1
answer
There are 10 professors and 20 lecturers out of whom a committee of 2 professors and 3 lecturer is to be formed.Find (d) In how many ways a particular lecturer is excluded
cbse
math
class11
ch7
permutations-and-combinations
exercise7-3
exemplar
q62-d
sec-a
easy
asked
May 19, 2014
by
sreemathi.v
1
answer
There are 10 professors and 20 lecturers out of whom a committee of 2 professors and 3 lecturer is to be formed.Find In how many ways a particular lecturer is included
cbse
math
class11
ch7
permutations-and-combinations
exercise7-3
exemplar
q62-c
sec-a
easy
asked
May 19, 2014
by
sreemathi.v
1
answer
There are 10 professors and 20 lecturers out of whom a committee of 2 professors and 3 lecturer is to be formed.Find In how many ways a particular professor is included
cbse
math
class11
ch7
permutations-and-combinations
exercise7-3
exemplar
q62-b
sec-a
easy
asked
May 19, 2014
by
sreemathi.v
1
answer
There are 10 professors and 20 lecturers out of whom a committee of 2 professors and 3 lecturers is to be formed. In how many ways can a committee be formed?
cbse
math
class11
ch7
permutations-and-combinations
exercise7-3
exemplar
q62-a
sec-a
easy
asked
May 19, 2014
by
sreemathi.v
1
answer
Ask Question
Tag:
Math
Phy
Chem
Bio
Other
SUBMIT QUESTION
►
Please Wait
Take Test
JEEMAIN Crash Practice
15 Test Series
NEET Crash Practice
15 Test Series
JEEMAIN
350+ TESTS
NEET
320+ TESTS
CBSE XI MATH
50+ TESTS
CBSE XII MATH
80+ TESTS
...