The centre of the third figure is empty. What digit should fit inside?

You have three orange, two pink and five purple balls in the drawer beside your bed. There is no electricity and the room is entirely dark. How many balls must you take out to ensure at least one ball of each colour at least?

The doctor prescribed you to take one pill from the bottle every half an hour. The bottle is now left with only three pills.

How long do you think you have before you run out of pills?

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's the probability of getting a king or a queen from a pack of 52 cards?

What is the largest amount of money that you can possess in change and still if someone asks you for a dollar, you won't be able to give?

I know a nine-letter word having only one vowel.
Do you ?

f you were running a race, and you passed the person in 2nd place, what place would you be in now?

What is the end of everything?

John killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?