There was a strange boy who was born before his father. How can this be possible?

A frog is at the bottom of a 30-meter well. Each day he summons enough energy for one 3-meter leap up the well. Exhausted, he then hangs there for the rest of the day. At night, while he is asleep, he slips 2 meters backwards. How many days does it take him to escape from the well?

What does a man do only once in his lifetime, but women do once a year after they are 29?

What is the next number in this series?

4,12,84,3612....

Can you make numbers like 24, using numbers 3,3,7 & 7 with any arithmetic operator?

Why is Saturday stronger than Monday?

Find a 9-digit number, which you will gradually round off starting with units, then tenth, hundred etc., until you get to the last numeral, which you do not round off. The rounding alternates (up, down, up ...). After rounding off 8 times, the final number is 500000000. The original number is commensurable by 6 and 7, all the numbers from 1 to 9 are used, and after rounding four times the sum of the not-rounded numerals equals 24.

What is the longest word in the dictionary?

If a zookeeper had 100 pairs of animals in her zoo, and two pairs of babies are born for each one of the original animals, then (sadly) 23 animals don’t survive, how many animals do you have left in total?

I am weightless, but you can see me. Put me in a bucket, and I'll make it lighter. What am I?