A type of mathematical puzzle in which the digits of an arithmetic exercise are replaced by lette

Course outline

A recreational mathematics magazine published from Belgium once introduced a cryptarithm in the following manner - "Cryptographers, to hide the meanings of messages, put digits in place of letters. As a form of retaliation, we will replace each digit of the following exercise with a letter." Cryptarithms are mathematical puzzles in which the digits appearing in an arithmetic exercise are replaced by letters, or sometimes by blank boxes. The task of the problem-solver is to reconstruct all the missing digits of the original exercise. In this course, we will look at cryptarithms built from addition, subtraction, multiplication and division exercises. Solving cryptarithms is like doing challenging detective work, and it can thus not only help children enjoy analyzing arithmetic exercises (which can otherwise seem boring), but can be a fun challenge even for adults.


A basic knowledge of how to add, subtract, multiply and divide whole numbers is all that you need, in addition to some logical reasoning. 

1. What is a cryptarithm?
2. Addition cryptarithms
3. Subtraction cryptarithms
4. Multiplication cryptarithms
5. Division cryptarithms

Omkar Deshpande

Omkar started The Young Socratics to try a different approach to teaching the regular middle and high school curriculum, which would not be compartmentalized, feel burdensome or boring, or devoid of joy and meaning. During the six years he spent at Stanford University towards his MS and Ph.D in computer science, he also attended classes and talks by professors in widely different disciplines (especially the humanities), and did interdisciplinary research spanning computer science, genetics and cultural anthropology. He came to believe that discipline boundaries, though convenient for specialists, prevent one from appreciating the interconnected nature of all human knowledge. He firmly believes in blending the teaching of math and science with the humanities (with a special emphasis on history and philosophy), without sacrificing the development of practical problem-solving skills. He earned his BS in Computer Science from the Indian Institute of Technology, Delhi, and is currently working as a Principal Engineer at WalmartLabs (formerly Kosmix).