The cover pertains to a rather hot topic at the club of late: divisibility. Can you see how the cover relates to divisibility?
Much of this issue’s content pertains to divisibility. There’s an explanation of how all the standard divisibility rules learned in school (typically for 2, 3, 4, 5, 8, 9, 10, and 11) are all instances of a uniform method, and this method is used to get divisibility rules for less common divisors like 7 and 27. Test your understanding of the material with a problem set on divisibility rules. Can you quickly tell what remainder results when you divide
by 7? (And extra credit if you can guess what inspired this sequence of numbers!)
Math Doctor Bob continues his series on Fermat’s little theorem, which is also about divisibility. He gives Euler’s generalization of Fermat’s little theorem and presents a beautiful proof of the result due to James Ivory.
The second half of our interview with Radmila Sazanović touches on some of her views on the relationship between art and math.
Emily Riehl provides proofs of theorems pertaining to the stable marriage algorithm…again adorned by drawings of Julia Zimmerman. Dr. Riehl also describes the results she proves in this part in her WIM Video.
Coach Barb continues her conquest of fractions, this time by looking at reciprocals in more depth. 3/7 makes a claim without proof, but not to fear, Anna B. provides a proof in Anna’s Math Journal.
Also inside, we describe two different solutions to part of the fifth Invention from the previous issue, one solution due to Girls’ Angle mentor Luyi Zhang.
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