When can we add 2 to 11 and get 1 as the correct answer?
You order chicken wings at KFC in the boxes of 6, 9 and 20. What is the largest number of wings that you cannot obtain by buying in any combination of the boxes?
What mathematical symbol can be put between 5 and 9, to get a number bigger than 5 and smaller than 9?
If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?
Yesterday I fell from 30 feet high ladder but I don't get hurt. Why?
A high school has a strange principal. On the first day, he has his students perform an odd opening day ceremony:
There are one thousand lockers and one thousand students in the school. The principal asks the first student to go to every locker and open it. Then he has the second student go to every second locker and close it. The third goes to every third locker and, if it is closed, he opens it, and if it is open, he closes it. The fourth student does this to every fourth locker, and so on. After the process is completed with the thousandth student, how many lockers are open?
A mile-long train is moving at sixty miles an hour when it reaches a mile-long tunnel. How long does it take the entire train to pass through the tunnel?
Transform the word THINK into BRAIN while changing only one letter at a time in a manner that each of the word in the process is a real word!!!
You are given with the following sum. Each of the letters can be decoded as a digit. If we tell you that D = 5, then can you solve it entirely?
DONALD
+GERALD
=ROBERT
Our product and our sum always give the same answer. Who are we?
There is a cryptic organization called Cicada 3301 that posts challenging puzzles online, possibly to recruit codebreakers and linguists.