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IN HONOUR OF Maths Week, as is our annual tradition, we’re setting our readers some puzzles. Give them a go!
Jack and Jill
The Ancient Greeks made enormous strides in the development of geometry.
The Greek mathematician Euclid works forms the basis for much of traditional geometry, relying on axioms and postulates to develop theorems that described properties and relationships of lines and shapes. Euclid’s Elements was the standard work on geometry for over two thousand years.
Lesser known is Hero of Alexandria who lived in the 1st Century CE and was a mathematician and engineer. While he did give us a useful formula for the area of a triangle, he also came up with a beautifully solution to what is now known as Hero’s problem, which we will pose as follows.
Jack and Jill live in houses some distance apart on the same side of a very straight river. Jack must visit Jill but on the way fetch a pail of water from the river.
Jack, very reasonably, wants to know how to find the shortest total journey.
Hero found a method without complex mathematical techniques. Can you?
Friday’s puzzles: The answers
1. Area of red square = 64 square metres
2. A rectangle 10m x 4m with a 0.5m path around it is actually a rectangle 11m x 5m = 55 square metres.
3. b) One 16-inch pizza has an area of 201 square inches, while one 10-inch pizza has an area of 78 inches. Two 10-inch pizzas therefore would only give you 157 square inches.
Come back tomorrow for the answers to today’s puzzle.
The puzzles this week have been compiled for The Journal by Eoin Gill of Maths Week Ireland and South-East Technological University (SETU).
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Taken far too soon!
@Frank Mc Carthy: sadly missed by small number of relatives.
@Frank Mc Carthy: good enough for him frankie
Poor aul divil RIP
@Tired Jim: your next if you keep posting that drivel
@Phillip Smyth: me think he has passed away already.
Struck down in the prime of his life! RIP
@John K: you waited til he died to say that, knowing he would absolutely batter you at 111 years old if you said it then.
@Maximilian Kolbe: my reply where I jokingly claimed to beat this gentleman up when he was 110 was obviously deemed toxic and removed! Just to clarify for the staff at the Journal, I did not assault the former oldest man in the world.
@John K: you’re a dangerous man.
Some milestone. Rest in peace sir.
I’m just here for the comments & my God I’m not disappointed.
@Matt D: I’m waiting for the comment… sure he smoked 40 a day and drank whiskey, and it did no harm..
@Matt D: some very very sad people around not every person gets to that age
@Matt D: Very toxic
@Clare Power: 40 fags a day!? You’d better get your facts right: it was a hundred a day & didn’t knock a feather out of him. He had just finished re-roofing his house 2 days earlier & his great great great granddaughter said she had never seen him looking so alert and sprightly.
@Patrice Ahern: lol
Thoughts and prayers.
@Jack Hayes: Prayers. That’ll help.
I will live to that age if it kills me.
This constant back and forth accusations of people being multi account trolls is getting extremely tiresome and is ruining every comments section. Please stop – on both sides!
@Soundy Sound: I think it would be more accurate to say that one individual, a multi-account troll, is ruining every comments section, and has been doing so for a long time. Of course there are false accusations in the other direction, but I do think this person needs to be challenged.
@Soundy Sound: Especially as The Journal does nothing about the problem.
@Brendan O’Brien: deflection as usual brenny…..all to get more £€$ …. despicable what you’re doing to this valued site
@Brendan O’Brien: I’ll NEVER TAKE THE BAIT—- you won’t score €€€ from me!!!!!, but keep trying, lol
@Frank Mc Carthy: You can keep reporting the comments Multi ID troll but it’s not gonna save you.. times up Ken,Buster, Frank Kevvy … lol
@Soundy Sound: That’s all well and good Soundy sound.. but we literally have one guy assuming Multi IDs and often other usernames IDs to spam this comments section for over a year now. As he’s called out on it, he ramps up his account numbers and starts attacking genuine posters. He has a serious issue.. and you’re right he is ruining this comments section. I suggest you look at the proof.. as if it were needed.. and act accordingly..
@Brian: you ruin it Brenda you filthy slag
@Soundy Sound: There is no back n forth,it’s people pointing out the one gobdaw that is multi account spamming. The Journal has completely failed in its duties so direct your anger at them.
Fair play he seen it all
Rip what he must has seen and lived throughout his life, unlike the trools here
@The Gate Florist: yes indeed the mind boggles what tales he could tell and monumental events in history over a century.
Rip great age got too. Got to see so much change
As Joe (so to speak) Duffy would say, “A young man” and he might, just might, add “so to speak”, so to speak.
If that was in Ireland chances are he passed 20 years ago and the family still pulling the pension each week.
At what age do you start looking over your shoulder for Conor McCloud?
have your say