What work can one never finish?

I throw two dice simultaneously.

What is the probability of getting a sum as 9 of the two numbers shown?

An infinite number of mathematicians are standing behind a bar. The first asks the barman for half a pint of beer, the second for a quarter pint, the third an eighth, and so on. How many pints of beer will the barman need to fulfill all mathematicians' wishes?

If it took eight men ten hours to build a wall, how long would it take four men to build it?

All of you like to eat me. I am a five-lettered word. Remove the first two and I turn into an infamous animal. Remove just the first and I become a heinous crime. Remove the first and the last and you can groove on me.

Can you guess who am I?

A boy was driving a car, a girl took a lift from her. She asked his name. The boy said - my name is hidden in my car’s number, find it if you can. After this, she got down Car number was [ WV733N ] Can you guess the name now?

What is wrong in the below Picture?

Always in you, Sometimes on you;

If I surround you, I can kill you.

What am I?

What will be the best approach to finding all the prime numbers less than 75 that leave an odd reminder when we divide them with 5?

If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?