You see a boat filled with people, yet there isn’t a single person on board. How is that possible?

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?

Before the start of the car race, John and Jacob have the same amount of fuel in their car. With this fuel, John can drive for 4 hours while Jacob can drive five hours.
After a time they realize that the amount of fuel left in John's car is 1/4th of the fuel in Jacob's.

For how long they are racing?

A Doctor always sneezes before the rain. Doctor sneezes, Will it rain?

Which flower has two lips?

These types of puzzles are known as charades. What you have to do is find two words that are referred to in the first stanza and the second stanza and put them together to form the third word in the third stanza.

Just for example, if my first refers to 'off' and my second refers to 'ice', then my whole will be office.

My first is present - future's past -
A time in which your lot is cast.

My second is my first of space
Defining people's present place.

My whole describes a lack of site -
A place without length, breadth, or height.

There is something which is always coming but never arrives?

The average age of 10 members of a committee is the same as it was 4 years ago, because an old member has been replaced by a young member. Find how much younger is the new member ?

There’s a one-story house in which everything is yellow. Yellow walls, yellow doors, yellow furniture. What colour are the stairs?

Why is Saturday stronger than Monday?