Two (perhaps) quick(ish) ways to multiply two digit numbers in your head

🏃🏻❌💡 While tutoring students who are in the process of multiplying two numbers, I sometimes challenge myself by trying to do the multiplication in my head instead of using a calculator. I don't know where I learned it, but I usually take a divide-and-conquer approach to multiplying large numbers, a large number for me being … Continue reading Two (perhaps) quick(ish) ways to multiply two digit numbers in your head

Ebook Mystery Word Problem!

💻🤔📕 I have recently been reading an ebook* that is quite long and has endnotes. Because my ebook reader only tells me my current positions in the actual body of the book and the endnotes, I have been wondering how much of the book I have actually read. Right now, my reader tells me I'm … Continue reading Ebook Mystery Word Problem!

To cross multiply or not cross multiply

When I was in Grade 7 our homeroom/math teacher told the class in a hushed voice, “Don’t cross multiply.” At the time I didn’t understand what he meant, nor did I likely understand what cross multiplication was. Ever since I have occasionally wondered why he would admonish students from using such a useful tool. Cross-multiplication … Continue reading To cross multiply or not cross multiply

Algebraic Expressions vs Algebraic Equations

Give the algebraic expression that represents the perimeter of the following polygon.  Over the last five years working as a tutor I have seen many students struggle with a problem like the one above. To answer it we must remember that the perimeter of any shape can be found by adding up its side-lengths. With side-lengths that … Continue reading Algebraic Expressions vs Algebraic Equations