Solution:

3^2 = 4 + 5
(^ is used for squaring the term, it is not used here as a mathematical symbol.)

Solution:

There are sixty marks in the given figure, thus it is safe to assume that each mark represents a minute.

Now, the hour hand is on a mark when the minute hand is on [0, 12, 24, 36, 48]. When the minute hand is on a mark, the second hand is on noon. But the orange hand cannot be the second hand. (It would be onnoon and it would be eighteen minutes past/before a full hour.)

a) Purple is on 12. Green indicates twenty four minutes. orange indicates forty two [minutes] = 8 + 2/5 [hours] = 8:24
b) Purple is on 12. Green indicates thirty six minutes. orange indicates eighteen [minutes] = 3 + 3/5 [hours] = 3:36
c) Green is on 12 = 3:36
d) Green is on 12 = 8:24.

Please note that the watch could be rotated upside down as well.

Solution:

It is simple. The sheriff never told him where the crime scene was. But still he reached at the right place. This points towards the fact that he knew it already and that he is the killer himself.

Solution:

If you look into the picture, you can see the cut lines. If the four people cut along with the lines, each one of them will have 1/5th of the cake.

Solution:

If you take a look closely, you will acknowledge the fact that every symbol in the given figure is somehow associated with the surrounding one’s position. The upside-down spade is used to the left of a right-side-up heart every time.

Solution:

He should draw any chit of paper and before unfolding it, he must eat and swallow the chit. In this manner, to determine the judgment of the god, they will have to look at the other chit which will have 'Guilty' written over it. Thus everyone will believe that the chit which he ate had innocent written over it and thus they will believe that he is innocent.

Solution:

The first figure tells you where you have to make the cut in the paper. Now you have two pieces of paper. If you rotate the right piece to 180 degrees, you will get what is shown in the figure two. Now the hole is in the center of the paper.

Solution:

The 100th statement for sure is incorrect because it says that at least 100 of the statements are incorrect.

Suppose if that is correct, then 100 statements cannot be true.
This suggests that the 100th statement is incorrect and that the first statement is true.

Similarly 99 statements cannot be true because if they were true, then two statements would become correct i.e. the 1st and the 99th.
But the 99th statement says that at least 99 are incorrect.
This suggests that the 99th statement is incorrect and that 2ndone is true.

If we keep analyzing is the same way till the end, we will find out that only the first fifty statements are true and all the remaining ones are incorrect.

Solution:

Solution is below

Solution:

At every floor, the detective had to open the window himself. If the man had committed suicide, then at least one of the windows must have been open. A person who is committing suicide won’t close the window behind him. Thus he knows that someone pushed him off the edge and closed the window afterwards.