Can you find out which number multiplied by itself will give the output as 12345678987654321?

Spelt forwards I’m what you do every day, spelled backwards I’m something you hate. What am I?

There is a barrel with no lid and some wine in it. 'This barrel of wine is more than half full,' said Curly. 'No it's not,' says Mo. 'It's less than half full.' Without any measuring implements and without removing any wine from the barrel, how can they easily determine who is correct?

Can you find out the missing number?

? 4 5 3 5

9 5 7 10 3

In 1990, a person is 15 years old. In 1995, that same person is 10 years old. How can this be?

Can anyone tell me a word in the English dictionary which has a silent 'z'?

It is a 5 letter word if you take away first letter it is something you get from sun, if you remove second letter you will get something to eat, if you remove third letter you get a word you use in pointing at and if you remove the fourth letter you get something to drink. What is it?

A professor thinks of two consecutive numbers between 1 and 10.
'A' knows the 1st number and 'B' knows the second number

A: I do not know your number.
B: Nor do I know your number.
A: Now I know.

What are the four solutions for this?

John is the son of Jacob.
So,
Jacob is the_____of John's father?

Here is a mathematical expression that also secretly tells a movie name. What movie is that?