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 ...

Examples: (1) 475 is divisible by 25 but not by 125. (2) 465 is divisible by 5 but not by a higher power of 5. As 4 + 6 + 5 = 15, it is divisible by 3 though. (3) To check for divisibility of ...

The Mathematics Teacher (MT), an official journal of the National Council of Teachers of Mathematics, is devoted to improving mathematics instruction from grade 8-14 and supporting teacher education ...

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 ...

A curious query from a class 5 student about divisibility rule 8 in mathematics led to this government primary school teacher SursinhParmar to invent new divisibility rule 8 in maths. Representative ...

The Monthly publishes articles, as well as notes and other features, about mathematics and the profession. Its readers span a broad spectrum of mathematical interests, and include professional ...