Number Sense and Nonsense: Building Math Creativity and Confidence Through Number Play

Number Sense and Nonsense: Building Math Creativity and Confidence Through Number Play — page 9
1 Odds and Evens What This Chapter Is About All whole numbers are divided into two groups odd numbers and even numbers They follow one another in order odd even odd even like the page num bers in this book But sometimes an even number can be odd and an odd number can be even You will read about it in this chapter Knowing how numbers behave can give a big boost to your number sense That knowledge can help you discover when numbers are used in ways that make no sense or are nonsense You will learn when to expect an even number and when to expect an odd number as an answer to a problem in arithmetic The ancient Egyptians almost 4 000 years ago had a way of multiplying numbers using mostly even numbers You will learn it