John left on a horse on Thursday , was gone for two days, and came back on Thursday after completing his work. How did that happen?

There are people and strange monkeys on this island, and you can not tell who is who (Edit: until you understand what they said - see below). They speak either only the truth or only lies.
Who are the following two guys?
A: B is a lying monkey. I am human.
B: A is telling the truth.

What will be the best approach to finding all the prime numbers less than 75 that leave an odd reminder when we divide them with 5?

A and B have a certain number of chocolates with them. If B gives one chocolate to A, they will have an equal number of chocolates. But if A gives one chocolate to B, then A will be left with half the number of chocolates that B has.

Can you find out the number of chocolates they have right now?

Can you find the 09 errors in the picture below?

In the below-given picture of a pretty girl, there is something wrong. Can you find out what it is?

At my favorite fruit stand,
an orange costs 18,
a pineapple costs 27,
and a grape costs 15.
Using the same logic, can you tell how much a mango costs?

You and your two friends are working in a multinational company. How can you three find out the average salary of you all without disclosing your own salary to the other two?

81 x 9 = 801. What must you do to make the this equation true?

Can you count the number of children in the picture below