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.

On a bright sunny day, two fathers took their son fishing in the lake. Each man and son were able to catch one fish. When they returned to their camp, there were only three fishes in the basket. What happened?

PS: None of the fish were eaten, lost, or thrown back.

I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?

A 52% bias toss for head using the 51% tail bias coin was done to obtain a fair result.

Can you find how bias is the floor in this case?

I am the one who remains awake when you sleep. But I need to rest when you awake. Who Am I?

Give it food and it will live; give it water and it will die.

This is a simple one. You just have to count the number of Fs in the given sentence.

Finished Files are the result of years of scientific study combined with the experience of years.

How many did you count?

John left on a horse on Thursday , was gone for two days, and came back on Thursday after completing his work. How did that happen?

A worker is to perform work for you for seven straight days. In return for his work, you will pay him 1/7th of a bar of gold per day. The worker requires a daily payment of 1/7th of the bar of gold. What and where are the fewest number of cuts to the bar of gold that will allow you to pay him 1/7th each day?

Which tank will fill first?