Can you solve this amazing hard number series problem?
7, 8, 10, 12, 16, 18 ?

If two fifty-foot ropes are suspended from a forty-foot ceiling that is twenty feet apart, how much rope will you be able to steal if you have a knife?

A Scientist was fifty years old in the year 2000 but he was forty years old in the year 2010. How can this be possible?

PS: It has a logical answer.

Your mother’s brother’s only brother-in-law is asleep on your couch. Who is asleep on your couch?

In a rainy season, one day 3 huge ladies walked under a normal-sized umbrella.
The umbrella is not huge enough to accommodate all 3 ladies yet not a single lady got wet. Why?

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

Complete the table series riddle by finding the number that can replace "??".

This is the oldest riddle that I have heard.

Once there was a man who was travelling with a Tiger, goat and grass.
He needs to cross a river that can carry a maximum of two i.e. Man + one of Tiger goat or grass. But the problem is "If he takes the lion with him, the goat will eat grass and if he takes grass with him, the lion will eat the goat".

How can he ensure the safe delivery of all three?

Find the missing letter in the last circle logically in the given below picture.

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