Quickly Solve this riddle

7 - 4 + 3 * 0 + 1 = ?

A woman lives in a Tall building thirty-six floors high and served by several elevators which stop at each floor going up and down. Each morning she leaves her apartment and goes to one of the elevators. Whichever one she takes is three times more likely to be going up than down. Why?

Ten coins have been arranged as you can see in the given picture. In this arrangement, a triangle is formed pointing upwards. You have to invert the position of the triangle and make it point downwards while changing the position of 3 coins only. Can you do it?

What is the relationship between these matchstick pictures below?

I know a 5-digit number having a property that With a 1 after it, it is three times as large as it would be with a one before it.

Guess the number?

What word is pronounced the same if you take away four of its five letters?

On my way to St. Ives I saw a man with 7 wives. Each wife had 7 sacks. Each sack had 7 cats. Each cat had 7 kittens. Kittens, cats, sacks, wives. How many were going to St. Ives?

Can you convert the number zero(0) into a positive number using just one mathematical operator ?

What's the only room from which no one can enter or leave

In a certain country ½ of 5 = 3. If the same proportion holds, what is the value of 1/3 of 10?