# November, 2016

## Ask Uncle Colin: A Rational Mess

Dear Uncle Colin, I've got a ratios question, and I don't understand the solution. The question is: Three numbers, $x$, $y$, and $z$, have a sum of 871. The ratio $x:y$ is 4:5 and the ratio $y:z$ is 3:8. What is the value of $y$? Their solution is to say

## How The Mathematical Pirate Integrates By Parts

The student sighed. "$\int x^3 e^{-2x} \dx$", he said. "That's going to be integration by parts. And it's going to take three steps. What a pain." "Aharr!" swashbuckled the Mathematical Pirate. "That's what you think!" "It is what I think," said the student, slightly bemused. "Would you like to know..."

## Ask Uncle Colin: Should I Interrupt?

Dear Uncle Colin, Sometimes, my professors write wrong things on the board, and I'm never sure whether to correct them. On one hand, I feel like I should respect them and their work; on the other, if I say nothing, I worry that my classmates are getting bad information. What

## Wrong, But Useful: Episode 38

It’s your annual Wrong But Useful Big MathsJam Special! Recorded live, so the audio is a bit shaky in parts. @icecolbeveridge, @reflectivemaths and @peterrowlett discuss Tantrix with some excited background chatter Colin interviews @teakayb (Tom Briggs in real life), who’s at MathsJam with an Enigma machine @pecnut and @mscroggs (Adam

## Ask Uncle Colin: Dividing by decimals

Dear Uncle Colin, A question came up asking me to work out $4.5 + 1.5k = 18-3k$. Obviously, I can rearrange that to get $4.5k = 13.5$ - but how can I divide by 4.5 without a calculator? - Calculating A Number Turning On Ratio Hi CANTOR, and thank for

## Ask Uncle Colin: Why don’t you use ‘Dr’ on your books?

Dear Uncle Colin, Is there a reason you don’t use "Dr" in your author name? - Presumably Has Doctorate Hi, PHD! Thanks for your question. Yes, there are several reasons. The one I usually give is that my bank calls me Dr Beveridge and it makes me uneasy. It's also