# Browsing category puzzles

## A coin sequence conundrum

Zeke and Monty play a game. They repeatedly toss a coin until either the sequence tail-tail-head (TTH) or the sequence tail-head-head (THH) appears. If TTH shows up first, Zeke wins; if THH shows up first, Monty wins. What is the probability that Zeke wins? My first reaction to this question

## Ask Uncle Colin: Missing Numbers

Dear Uncle Colin, My teacher recently challenged me to tackle the missing numbers problem below and I don't know where to start! It's driving me to disgust with the whole number system. Crazy Old Numbers, Wacky And Yucky #Edtech and gimmicks won't help students solve this, but considering the nature

## A tennis puzzle

A puzzle that occurred to me watching Wimbledon this week: A tennis match goes to five sets. The number of games one of the players wins in each set forms an arithmetic series. Given that the two players won the same number of games in total, who won the match?

## A Gardner-esque puzzle

One of my favourite sources of puzzles at the moment is @WWMGT - What Would Martin Gardner Tweet? (Martin Gardner, in case you’re not up on the greats of popular maths writing, was one of the greats of popular maths writing - and is indirectly responsible for Big MathsJam.) Recently,

## Why you can’t get unlimited chocolate (at least like this)

December! That means it's time for CHOCOLATE! My dear friend Essbee showed me this: Free chocolate ahoy (and white chocolate, my favourite)! But surely there’s got to be a catch? Of course there’s a catch. You can’t just rearrange an area to end up with a bigger area - moving

## The semicircle puzzle

In a recent episode of Wrong, But Useful, I asked: A square is inscribed within a circle of radius $r$. A second square is inscribed within a semicircle of the same radius. What is the ratio of the areas of the squares? It's easy enough to find the side length