Ask Questions, Get Answers

Want to ask us a question? Click here
Browse Questions
Home  >>  CBSE XI  >>  Math  >>  Permutations and Combinations
0 votes

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 no girls

$\begin{array}{1 1}(A)\;20\\(B)\;21\\(C)\;22\\(D)\;23\end{array} $

Can you answer this question?

1 Answer

0 votes
  • $C(n,r)=\large\frac{n!}{r!(n-r)!}$
Total no of girls =4
Total no of boys =7
Total members in the team =5
$\therefore$ Total no of ways of selecting the team with 5 members which does not include girls =$7C_5$
$7C_5=\large\frac{7!}{5!\times 2!}$
$\Rightarrow \large\frac{7\times 6\times 5!}{2\times 1\times 5!}$
$\Rightarrow 21$ ways
Hence (B) is the correct answer.
answered May 15, 2014 by sreemathi.v

Related questions

Ask Question
student study plans
JEE MAIN, CBSE, AIPMT Mobile and Tablet App
The ultimate mobile app to help you crack your examinations
Get the Android App