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THIS PAST WEEK was Maths Week and if you’ve clicked in here, you’re probably one of the people who has been puzzling over the fiendish maths challenges that have run on TheJournal.ie every evening over the past seven days.
So here they are: the answers you ‘ve been waiting for.
Let us know how you did in the comments.
Sunday: The One About Dividing Up The Sweets
The answer: 60
One half is 30, one third is 20, one sixth is 10. If we take 10 from 30 and add it to 10 then everybody has 20.
Monday: The One About Organising The Building Of A Wall
The answer: 2 days
The faster worker finishes his wall in 4 days that means he builds 1/4 of a wall in a day. The second worker builds 1/6 of a wall in a day and the third builds 1/12 of a wall in a day. Between them they can build 1/4 + 1/6 + 1/12 of a wall per day. That is 6/12 or 1/2 of a wall per day. This means that they can build one wall in 2 days.
Tuesday: The One About The Sugar Tax
The answer: 35g in a 330ml can is 10.6g per 100ml so the sugar tax added will be 60c (30c per litre)
You would consume 365 x 35 g = 12,775 g. That’s over 12 kg (26 pounds or 1 stone 8 pounds) of unnecessary sugar from just one can of this sugared drink a day for one year. If you read your food labels you will see that this wouldn’t be the only source of sugar intake in your diet.
Wednesday: The One About The Number Of Games In A Tennis Tournament
The answers:
1) There will be 5 rounds. 32 players in 1st round, 16 in 2nd, 8 in 3rd, 4 in 4th, 2 in 5th (final).
1b) There will be 31 matches. If you think about it – in every match there will be a unique loser. The tournament will have 31 losers in all. That means that 31 matches will have to be played.
2) There will be 10 matches – the outer vertices (corners) below represent the players, the lines each represent one match or connection between the players.
Thursday: The One About The Currency Exchange
The answer: £100 costs €100/0.85 + commission = 117.64+ 1.27 = €118.92
£100 can be sold for 1.11 €/£ = €110 and the commission has to be paid from this, so you get €110 – 1.27 = €108.73 back. So, the whole business has cost you €10.19.
Friday: The One About The Snooker Balls
The answer: For 10 rows we will need 55 balls.
The method: You could count these in your head, but a formula can be discovered that will calculate for any number of rows.
The formula may be understood by looking at the diagram below. The balls can be rearranged into a right angled triangle. A duplicate of this can be inverted and placed alongside forming a rectangle. This has height the number of rows and as length the number of rows plus one. The number of balls in this rectangle is 6×5 which is 30 which is twice the number of balls in the 5 rows.
For one hundred rows the rectangle would be 100 x 101 = 10100. And half of this is 5050 which gives the number of balls needed for 100 rows.
Writing as a formula in mathematical form:
N = 1/2 n(n+1)
N = number of balls needed
n -= number of rows
Saturday: The One About Two Friends Running a 5KM
The answer: Ann runs 3 km. She runs one and a half times as fast as Bill, Therefore she will run one and a half times as far as Bill in the same time. That is in the ratio of 3 : 2. So Ann runs 3 km in the time that Bill runs 2 km.
Ann can lap Bill if she runs 15 km in which time Bill would run 10 km.
Gardai took the names and addresses of all the protesters in Cork I believe. Pity they didn’t do the same outside the four courts yesterday.
@Ger Buckley: miserable.
@Ger Buckley: According to some reports they did take some names outside the four courts yesterday. However on the last court date they did nothing to disperse the crowd of 100 supporters who did not obey social distancing. The same day they told Debenhams workers to go home even though they were abiding by the social distancing rule.
Anyone who has been working for Debenhams last 2 years should have k own their jobs were unsafe. They have been fighting liquidation a number of years now, been trying to stay afloat since the last recession.
The company was always going to go down this route it is only common sense from a business perspective.
The goverment will just have to cough up Staturtory reduncies
They were in trouble well before this, Covid 19 onlt brought closures forward.
@Paul O’Sullivan: Maybe then they shouldn’t have told the workforce that their jobs were safe 2 days prior to closing due to the virus.
@Anne Doddy: Really does it make a difference?
@Anne Doddy: they were safe for the time being, but Debenhams did not know that the government were ordering social distancing at this scale. They are not mind readers.
Debenhams were only surviving hand to mouth. On xmas takings and online sales,
This is a protest in relation to a matter that will be before the courts. We are allowed to comment.
Why can’t the Gemma O D lockdown case protests be covered and we have our say?
I’m on the Debenhams workers side and against the lockdown protests – but I think the same standard should apply.
@milton friedman: Media organisations have a responsibility to not host the sort of deranged lunacy that would occur if Gemma supporters are invited to comment such as encouraging people to ignore instruction from Gardai or to do the exact opposite to medical advice.
@milton friedman: because she’s a gobsh*te and it would only entice other gobsh*tes to comment.
@milton friedman: because Milton it’s news, just not the type of news that the journal or any other Irish broadcaster will touch with a barge pole, easier to call them cranks/ nutjobs
@Rochelle: all due respect that whether it’s true or not that ‘deranged lunacy’ is a matter of your opinion.
@Michael Byrne: yeah I take it that they don’t want a civil liberties debate, even though most are complying …
@milton friedman: Take a look at this video. She shouldn’t be allowed any publicity at all. Mind blowing how daft she is https://youtu.be/98Y1upsb1ZU
@Ken Oath: no it’s not opinion, mad as a bag of frogs
@milton friedman: Fair play to you Milton!
@M: thanks for the vid. Don’t know how you found it. I thought she had her accounts deleted or is this a new one they haven’t caught up with yet
@M: cheers, hadn’t see this one.
@Micheál: I do my part
@M: Freedom Fighter
British company thats using the pandemic as an excuse to walk away and not pay a brown cent of
redundancy to staff and the government are powerless to stop them. On a side note another British company Euro car parts formally known as PR Reillys Operating in Ireland are about to pull the same stunt and watch more will follow suit.
@Porter Mechanic: But hey. The shareholders are happy. Great system. Screw the many for the few
@Louis Jacob: the value of the stock is now negligible. I can assure you that the shareholders are not happy.
@richiecranium: Can you show me where you learned that? Or are you assuming it?
@Louis Jacob: companies that go bust lose all their value. All shareholders will have lost all of their investment. Sure why wouldn’t you just invest in bad companies if it was all just a big money maker? People who have no idea about the stock market should refrain from commenting on the stock market.
@richiecranium: Peiple who revere the stock market should refrain from commenting about what other people should do. And you were doing so well.
@Louis Jacob: Debenhams shares have been trading at 3p for the last year, they were doomed either way. It’s not the greedy shareholders to blame either, it’s consumers who can get things cheaper online than in high street stores like Debenhams.
@Gordon Comstock: Thanks Gordon. I dont really know that much about the stock market. I’m just bored and cranky.
@Louis Jacob: I don’t “revere” the stock market but I do understand it’s utility. There are no winners here except maybe the liquidation firm who’ll make a few bob off closing the company down.
@richiecranium: Stop commenting.
@richiecranium: Why did you use parentheses when you didn’t need to? You should stop using them you arrogant twit.
@Porter Mechanic: is that the same Euro carparks that is currently using its drivers to deliver supplies for the HSE? Also how would you know?
@Louis Jacob: sorry for hurting your feeling Louis I didn’t mean too.
@richiecranium: You didnt hurt my feelings. I just called you an arrogant twit because only arrogant twist do the parenthesis thing. If you’re own feelings weren’t hurt why do you keep coming back for more?
@Louis Jacob: your
@Louis Jacob: well that language was very hurtful and mean. You should be nicer to people next time but I forgive you. We can be friends.
@Louis Jacob: https://markets.businessinsider.com/stocks/debenhams-stock
down from £1.32 5 years ago to 2p now….
@Wheresmyjumper: Car Parts……..
@richiecranium: I apologise. I know that arrogance stems largely from insecurity. I shouldn’t have let my sensibilities get the better of me.
@ihatehens: My bad but to be fair i was going for particularly hard stool at the time of reading and typing
@Porter Mechanic: already owns m to revenue do where do they get redundancy payments from. Should have been shut ages ago
@Louis Jacob:where is the Irish company listed for you to make that comment
@Louis Jacob: yea just make silly comments you can’t backup
@james foley: Get with the program man. I was corrected and acknowledged that about 4 hours ago.
@Porter Mechanic: Any link or source for ECP/Reillys pulling out?
It’s a disgrace the way the workers are treated people in Ireland should stop buying online from Debenhams
It wasn’t a secret that debenhams was in trouble, It sucks for the staff, but i don’t see what was deceiving?
Got an email from their newsletter saying their online store is still in business so what’s going on?
@MitchConnor: Think all of the online stuff comes directly from the UK.
I would advise the workers to appoint their spokesperson rather than providing a platform for politicians who are likely to alienate their supporters.
have your say