A network of 20 x 10 squares is given to you. Can you calculate how many unique squares and rectangles can be formed combining two or more individual squares ?
What is the longest word in the dictionary?
Railroad Crossing, look out for the cars. Can you spell that, without any R's ?
You walk into a room that contains a match, a kerosene lamp, a candle and a fireplace. What would you light first?
The person who makes it has no need for it; the person who buys it has no use for it. The person who uses it can neither see nor feel it. What is it?
What month of the year has 28 days?
Take away my first letter, then take away my second letter. Then take away the rest of my letters, yet I remain the same. What am I?
How many letters are in the alphabet?
John was going on a jungle trip. He asked his wife to pack something to eat, something to drink and something to burn if he feels cold in the jungle. When John opens the backpack he found just one thing in the bag. What was it?
I go up and I go down. I go up towards the beautiful sky and down toward the green ground. I am present tense. I am past tense too Children love me. Who Am I?
I possess a head I flaunt a tail But I don't have mouth or legs Can you find out who I am?
There is a cryptic organization called Cicada 3301 that posts challenging puzzles online, possibly to recruit codebreakers and linguists.