Question

6 books are kept one on top of the other. B1 and B2 are always kept together. 3 books are kept above B5. B6 is neither placed at the top nor at the bottom. B1 and B2 cannot be placed with B5. Which book is kept at the bottom?
1. B1 or B3
2. B2 or B3
3. B3 or B4
4. B1 or B4

Answer 1

Correct Answer - Option 3 : B3 or B4

Six books are kept one above the other.

i) 3 books are kept above B5.

B5

 

ii) B1 and B2 are always kept together.

ii) B1 and B2 cannot be placed with B5. (This means it cannot come below B5 thus it can only be placed either at 1 or 2).

B1 / B2

B1 / B2

B5

 

iii) B6 is neither placed at the top nor at the bottom. (This means only 2 positions are left i.e either 3rd or 5th).

B1 / B2

B1 / B2

B6

B5

or

B1 / B2

B1 / B2

B5

B6

 

The final arrangement will be:

B1 / B2

B1 / B2

B3 / B4

B5

B6

B3 / B4

 

Thus we left with B3 and B4 which can be placed at the bottom.

Hence, the correct answer is "B3 or B4".