The crisp new dollar bill that I have just taken from my wallet bears the serial number 24598176. It’s easy to tell that the number is exactly divisible by 2 but not by 5. Is it divisible by 3? by 4?

It’s easy to tell if a given whole number is divisible by 2. Just check whether the last digit is even. There are also simple rules to determine whether a number is ...

Randomly scramble the digits 0, 1, 2, 3, 4, 5 and 6 to form a seven-digit number (or a six-digit number if the leading digit is 0). Rank the following events in order ...

Learn how to check divisibility by 13 with Sall's Theorem! This easy-to-follow method helps you determine if a number is divisible by 13 without doing long division. Perfect for math enthusiasts and ...

This is a preview. Log in through your library . Journal Information The Mathematics Teacher (MT), an official journal of the National Council of Teachers of Mathematics, is devoted to improving ...