Solution:

Thursday

The only days the Tiger can say that he lied on the previous day are Mondays and Thursdays. The only days the Elephant can say this, are Thursdays and Sundays. Therefore, the only day they both say that is on Thursday.

Solution:

Hockey Stick $49.50 & ball $0.50

Solution:

It has been clearly mentioned that all the boxes are labeled incorrectly. If he opens the Box3, then he will get either Dark Chocolates or Milk Chocolates as it is labeled incorrectly. Let us suppose he finds Dark Chocolates in there. Now since all are labeled incorrectly, Box B A must contain Milk Chocolates and Box B must contain Milk Chocolates and Dark Chocolates.

Solution:

If the man killed himself, he would not have been able to rewind the cassette. Thus it is clear someone else killed him.

Solution:

The husband had booked two tickets for departure and only one for the return. The travel agent told this information to the police and they immediately came to know that he had planned the murder right from the beginning.

Solution:

It can be solved as below.

Solution:

Solution can be verified from the picture below.

Solution:

100

Series of number that do not contain albhabet 'T'

Solution:

There is a simple logic to solve this question.
The size of the chocolate is 2 x 8. Thus, you need to have 2 x 8 = 16 pieces.
Every time you break the chocolate, you will get one extra piece.
Thus, to get 16 pieces, you must break it (16 - 1) = 15 times.

Solution:

The password is U472BMT.

Read aloud the line and you will sound something like "U Four Seven 2 B M T".

Solution:

The stranger said that he thought the room was his. If so, he must have had the keys to the room and thus he must not have knocked.