How can you make number one disappear by adding something to it?

An American nightclub called 'The Coconut Grove' had a terrible fire in which over 400 people died. A simple design flaw in the building led to a high death toll. Subsequently, regulations were changed to ensure that all public buildings throughout the country eliminated this one detail, which proved deadly. What was it?

How many bananas can you eat if your stomach is empty?

You have three orange, two pink and five purple balls in the drawer beside your bed. There is no electricity and the room is entirely dark. How many balls must you take out to ensure at least one ball of each colour at least?

Which is heavier: a ton of bricks or a ton of feathers?

Replace The Question Mark Below With the Correct Number.

2 {38} 3
4 {1524} 5
6 {3548} 7
8 {????} 9

4 fathers, 2 grand-fathers and 4 sons went to watch the movie.What is the minimum number of tickets they need to buy ?

A generous owner of a company decided to give a bonus of $45 to every man and $60 to every woman on his birthday. But only one-ninth of the men and one-twelfth of the women were present to take the bonus.

Can you calculate the amount of money the owner spent if there were 3552 employees?

When monkey rotate the gear, which mark will be hit 1 or 2 ?

Using Only Five 5's and any mathematical operator make sum as 37