You need to arrange three 7 and mathematical symbols to form number 1?
What mathematical symbol can be put between 5 and 9, to get a number bigger than 5 and smaller than 9?
Many have heard it, but nobody has ever seen it, and it will not speak back until spoken to. What is it?
How many cubic feet of dirt are in a hole of one foot deep, three feet long, and two feet wide?
How many times can you subtract the number 5 from 25?
There are 2 sand hourglasses. The small one can measure 5 hours and the large one can measure 7 hours. How can we measure 16 hours with 2 sand hourglasses running together ?
Complete the series by replacing "?" with the correct number. ST ND RD TH '?'
What Deficiency does the below rebus represent? VIT_MIN
What English word has three consecutive double letters?
A man dies of old age on his 25 birthday. How is this possible?
What can you catch but never throw?
There is a cryptic organization called Cicada 3301 that posts challenging puzzles online, possibly to recruit codebreakers and linguists.