How many bricks does it take to complete a building that is 15 feet wide, 30 feet deep, and 12 feet tall made of brick?

John was working on a Chemical Mixture whose weight comprise 90% liquid and 10% solid. The total weight of the mixture is 20 pounds. After a while, John noticed that some of the liquid evaporated and now the liquid comprises just 50% of the weight.

What is the weight of the chemical mixture now?

A new clothing store has a unique method of pricing items. A vest costs $20, a tie costs $15, a blouse costs $30, and underwear costs $45. How much would pants cost?

What does a man do only once in his lifetime, but women do once a year after they are 29?

It's a 7-letter word.
If we remove 1 letter from it, it remains the same.
If we remove 2 letters from it, it remains the same.
If we remove 3 letters from it, it remains the same.
If we remove all the letters from it, still it remains the same.
What is it?

What occurs twice in a week, once in a year but never in a day?

You have two strings whose only known property is that when you light one end of either string it takes exactly one hour to burn. The rate at which the strings will burn is completely random and each string is different.

How do you measure 45 minutes?

How many times can you subtract the number two from the number fifty?

Which is the smallest number that you can write using all the vowels exactly once?

How do you go from 98 to 720 using just one letter?