mscroggs.co.uk
mscroggs.co.uk

subscribe

Blog

 2019-09-01 
This week, I've been in Cambridge for Talking Maths in Public (TMiP). TMiP is a conference for anyone involved in—or interested in getting involved in—any sort of maths outreach, enrichment, or public engagement activity. It was really good, and I highly recommend coming to TMiP 2021.
The Saturday morning at TMiP was filled with a choice of activities, including a treasure punt (a treasure hunt on a punt) written by me. This post contains the puzzle from the treasure punt for anyone who was there and would like to revisit it, or anyone who wasn't there and would like to give it a try. In case you're not current in Cambridge on a punt, the clues that you were meant to spot during the punt are given behing spoiler tags (hover/click to reveal).

Instructions

Each boat was given a copy of the instructions, and a box that was locked using a combination lock.
The instructions, download a pdf here.
Locked boxes.
If you want to make your own treasure punt or similar activity, you can find the LaTeX code used to create the instructions and the Python code I used to check that the puzzle has a unique solution on GitHub. It's licensed with a CC BY 4.0 licence, so you can resuse an edit it in any way you like, as long as you attribute the bits I made that you keep.

The puzzle

Four mathematicians—Ben, Katie, Kevin, and Sam—each have one of the four clues needed to unlock a great treasure. On a sunny/cloudy/rainy/snowy (delete as appropriate) day, they meet up in Cambridge to go punting, share their clues, work out the code for the lock, and share out the treasure. One or more of the mathematicians, however, has decided to lie about their clue so they can steal all the treasure for themselves. At least one mathematician is telling the truth. (If the mathematicians say multiple sentences about their clue, then they are either all true or all false.)
They meet at Cambridge Chauffeur Punts, and head North under Silver Street Bridge. Ben points out a plaque on the bridge with two years written on it:
"My clue," he says, "tells me that the sum of the digits of the code is equal to the sum of the digits of the earlier year on that plaque (the year is 1702). My clue also tells me that at least one of the digits of the code is 7."
The mathematicians next punt under the Mathematical Bridge, gasping in awe at its tangential trusses, then punt along the river under King's College Bridge and past King's College. Katie points to a sign on the King's College lawn near the river:
"See that sign whose initials are PNM?" says Katie. "My clue states that first digit of the code is equal to the number of vowels on that sign (The sign says "Private: No Mooring"). My clue also tells me that at least one of the digits of the code is 1."
They then reach Clare Bridge. Kevin points out the spheres on Clare Bridge:
"My clue," he says, "states that the total number of spheres on both sides of this bridge is a factor of the code (there are 14 spheres). My clue also tells me that at least one of the digits of the code is 2." (Kevin has not noticed that one of the spheres had a wedge missing, so counts that as a whole sphere.)
They continue past Clare College. Just before they reach Garret Hostel Bridge, Sam points out the Jerwood Library and a sign showing the year it was built (it was built in 1998):
"My clue," she says, "says that the largest prime factor of that year appears in the code (in the same way that you might say the number 18 appears in 1018 or 2189). My clue also says that the smallest prime factor of that year appears in the code. My clue also told me that at least one of the digits of the code is 0."
They then punt under Garret Hostel Bridge, turn around between it and Trinity College Bridge, and head back towards Cambridge Chauffeur Punts. Zut alors, the lies confuse them and they can't unlock the treasure. Can you work out who is lying and claim the treasure for yourself?

The solution

The solution to the treasure punt is given below. Once you're ready to see it, click "Show solution".

Show solution

Similar posts

Christmas card 2020
Christmas card 2019
Christmas card 2018
Christmas card 2017

Comments

Comments in green were written by me. Comments in blue were not written by me.
 Add a Comment 


I will only use your email address to reply to your comment (if a reply is needed).

Allowed HTML tags: <br> <a> <small> <b> <i> <s> <sup> <sub> <u> <spoiler> <ul> <ol> <li>
To prove you are not a spam bot, please type "ratio" in the box below (case sensitive):

Archive

Show me a random blog post
 2021 

May 2021

Close encounters of the second kind

Jan 2021

Christmas (2020) is over
 2020 
▼ show ▼
 2019 
▼ show ▼
 2018 
▼ show ▼
 2017 
▼ show ▼
 2016 
▼ show ▼
 2015 
▼ show ▼
 2014 
▼ show ▼
 2013 
▼ show ▼
 2012 
▼ show ▼

Tags

oeis pythagoras dataset game of life boundary element methods ternary numerical analysis hats radio 4 wave scattering data visualisation mathsjam talking maths in public sorting interpolation estimation royal institution the aperiodical convergence determinants python php numbers martin gardner big internet math-off countdown ucl hexapawn royal baby braiding plastic ratio inverse matrices chalkdust magazine pizza cutting weak imposition wool propositional calculus programming puzzles triangles menace tmip simultaneous equations platonic solids matrices football bodmas matrix multiplication asteroids folding tube maps sound curvature quadrilaterals coins accuracy speed european cup golden spiral pac-man stirling numbers cross stitch bubble bobble a gamut of games frobel captain scarlet realhats chebyshev misleading statistics logs geogebra pascal's triangle squares game show probability draughts approximation bempp manchester science festival world cup london news christmas card go stickers weather station folding paper final fantasy graph theory phd mathslogicbot people maths reuleaux polygons javascript inline code nine men's morris data light mathsteroids raspberry pi national lottery flexagons london underground dragon curves sport statistics craft latex noughts and crosses chess advent calendar polynomials map projections gerry anderson hannah fry matrix of cofactors binary dates finite element method recursion electromagnetic field graphs tennis trigonometry palindromes twitter rugby cambridge pi machine learning rhombicuboctahedron gaussian elimination computational complexity games matt parker books logic fractals preconditioning error bars signorini conditions harriss spiral golden ratio reddit probability manchester christmas guest posts video games arithmetic matrix of minors pi approximation day geometry exponential growth sobolev spaces

Archive

Show me a random blog post
▼ show ▼
© Matthew Scroggs 2012–2021