Aptitude Overflow
+2 votes
39 views
The number of ways of arranging 10 books on a shelf such that 2 particular books are always together is
asked in Quantitative Aptitude by (262 points) 5 25 | 39 views

1 Answer

+2 votes
Best answer

We can mark the particular books as S1 & S2.

And the other books as B1, B2, B3, B4, B5, B6, B7, B8.

The particular books are always together.

So, we can arrange this (8 + 1) = 9 books in 9! way in the shelf AND the particular books can itself arranged in 2! ways.

So, Total ways = 9! * 2!

answered by (5.6k points) 7 18 131
selected by

Related questions

2,807 questions
1,179 answers
441 comments
40,069 users