The puzzles in this app are taken from the book by Sergiy Klymchuk Money Puzzles: On Critical Thinking and Financial Literacy that has been published in nine countries - New Zealand, USA, Germany, Ukraine, Mexico, Singapore, Korea, China and India. The puzzles are designed to both educate and entertain with surprising answers and unexpected solutions. The calculations are easy: one needs to know only the four basic arithmetic operations with whole numbers. The emphasis is on different ways of thinking, in particular, critical, lateral, commercial, and other ways of thinking. The skills that can be gained from solving the puzzles are very practical and will benefit anyone, no matter what they are doing.