Permutations & Combinations · NDA previous year questions

2017 4 questions

1. Q182017 · 10 Sept 2017

   A tea party is arranged for 16 people along two sides of a long table with eight chairs on each side. Four particular men wish to sit on one particular side and two particular men on the other side. The number of ways they can be seated is

   1. A.$24\times 8!\times 8!$
   2. B.$(8!{)}^3$
   3. C.$210\times 8!\times 8!$
   4. D.$16!$
   Show answer

   Answer: C

2. Q472017 · 10 Sept 2017

   A man running round a racecourse notes that the sum of the distances of two flag-posts from him is always 10 m and the distance between the flag-posts is 8 m. The area of the path he encloses is

   1. A.$18\pi$ square metres
   2. B.$15\pi$ square metres
   3. C.$12\pi$ square metres
   4. D.$8\pi$ square metres
   Show answer

   Answer: B

3. Q1102017 · 10 Sept 2017

   How many different permutations can be made out of the letters of the word ‘PERMUTATION’?

   1. A.19958400
   2. B.19954800
   3. C.19952400
   4. D.39916800
   Show answer

   Answer: A

4. Q1112017 · 10 Sept 2017
   
   1. A.$\left[\begin{array}{cc}2+3i& 5\\ 7& 2-3i\end{array}\right]$
   2. B.$\left[\begin{array}{cc}2-3i& 5\\ 7& 2+3i\end{array}\right]$
   3. C.$\left[\begin{array}{cc}2-3i& 7\\ 5& 2+3i\end{array}\right]$
   4. D.$\left[\begin{array}{cc}2+3i& 5\\ 7& 2+3i\end{array}\right]$
   Show answer

   Answer: A