In a school, there are four subjects. Seventy percent of students study English, seventy five percent of students study Science, eighty five percent of students study Mathematics and eighty percent of students study Spanish.

Can you calculate the percentage of students that study all four subjects?

Can you move from MANILA to UGANDA in the shortest time? You need to follow the below rules:
Rule 1: You can change up to 3 alphabets at a time.
Rule 2: New words must be of 6 alphabets.
Rule 3: The new word formed must be a country or capital.

If we add four times the age of John four years from now to five times his age five years from now we get ten times his current age.

How old will John be two years from now?

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.

Kareena is older than Bipasha. Bipasha is younger than Karishma and younger than Katrina. Katrina is older than Kareena and Alonso, who are older than Karishma.If Alonso and Kareena are twins, who's oldest?

In the attached figure, you can see a chessboard and two rooks placed on the chess board. What you have to find is the number of squares that do not contain the rooks. How many are there?

Outside a massage parlour, there is a board that reads
"I only massage those who do not massage themselves."

Reading the above statement, does the masseur massage himself?

When it's bad luck to meet a black cat?

There are two words one resembles the "state of rest" and the other is related to "writing/reading material".

Can you name these two words which also sound similar?

You have a three-gallon and a five-gallon measuring device. You wish to measure out four gallons.