Next two numbers in the sequence?
4, 5, 9, 13, 22.....
I'm starting to think there's an error, because I can't see an answer.
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Why?
4, 5, 9, 13, 22, 35, 57.
4 + 5= 9 - ok
9 + ? = 13?????? 9 + 5 = 14 surely?
9 + 13 = 22 - ok
13 + 22 = 35
35 + 22 = 57
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"Why?"
'Cos there's a mistake
;-)
I'll see if the missus can work it out
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I hope there's a mistake, because I'm going to feel pretty dumb if not.
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It's a Fibonacci. Stick the missing 1 and 3 at the beginning and you'll see how it goes.
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I don't think it is. Because 13 is not the sum of 9 and 5.
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It kind of skips is the way I'd describe it.
So.
1 and 3 is 4
1 and 4 is 5
Skip
4 and 5 is 9
4 and 9 is 13
Skip
9 and 13 is 22
9 and 22 is 31
Skip Etc
Yes?
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Is a "skip" a number sequence?
Seems to me its being mangled to fit, mangled in a way the question has not asked for.
Last edited by: Zero on Mon 28 Sep 15 at 20:56
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Explained badly then. Add up two, skip a digit, add up two, etc
That's no better, is it. Too much Horlicks with cheese and onion crisps tonight, sorry.
But I bet I'm right.
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It's all hobgoblin to me!
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I'll ask my niece...she'll know
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Well, since I don't know what the answer is then I can hardly dispute yours.
But it seems a bit arbitrary.
I believe that a Fibonacci sequence must begin 0, 1, or 1, 1, so if you want a 1 and a 3 at the beginning then you need to choose between...
1, 1, 3, 4, 5, 9, 13, 22..
or
0, 1, 3, 4, 5, 9, 13, 22..
For the first the differences would be
0, 2, 1, 1, 4, 4, 9
and for the second..
1, 2, 1, 1, 4, 4, 9
Neither of which are particularly supportive of your suggested sequence.
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How about:
4 (take 1 squared and add once)
5 (take 2 squared and add twice)
9
13 (take 3 squared and add 3 times)
22
31
40 (take 4 squared and add 4 times)
56
72 etc
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Well now, that's worth thinking about. So I am....
I may be some time, as the Captain said.
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What's the point of the question?
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To teach children logical problem solving and familiarity with number manipulation.
Seems pretty worthwhile to me.
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>> To teach children logical problem solving and familiarity with number manipulation.
>>
>> Seems pretty worthwhile to me.
It is if its actually achievable by children. If its not, then it will make them phobic about number manipulation pretty damn quickly.
Last edited by: Zero on Mon 28 Sep 15 at 21:41
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>> If its not, then it will make them phobic about number manipulation pretty damn quickly.
Oh don't be so silly.
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>> >> If its not, then it will make them phobic about number manipulation pretty damn
>> quickly.
>>
>> Oh don't be so silly.
Well clearly she cant work it out, clearly you cant work it out, so all in all its a complete waste of everyones time and no-one learns anything, but hey
Whatever.
Last edited by: Zero on Mon 28 Sep 15 at 21:56
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Oh she certainly can't and I can't so far, and you may consider it a waste of your time. But phobia developing?
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>> Oh she certainly can't and I can't so far, and you may consider it a
>> waste of your time. But phobia developing?
>>
whatever
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>> Oh she certainly can't and I can't so far, and you may consider it a
>> waste of your time. But phobia developing?
If it's just one problem like that then probably not. But an expectation that any/every child can 'do' numbers will lead to exactly that scenario for some of them. Whether it's described as phobia or simply despair at constantly failing the outcome is much the same.
This is why the UK government's attempt to push every child through the 5 GCSE 'English Baccalaureate' is so stupid and misguided.
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Isn't that exactly the left wing thinking that stopped schools having races in case someone lost and completely bothered up the education system?
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"Isn't that exactly the left wing thinking that stopped .................."
Scary, innit?
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>> This is why the UK government's attempt to push every child through the 5 GCSE
>> 'English Baccalaureate' is so stupid and misguided.
You think that's a waste of time and effort?
Then give them all a half hour test at 11. Label the bottom 2/3 "thick", send the other third to selective schools and spend most of the money on them.
Doesn't sound like the sort of thing you would support Bromp!
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All children should try to pass their exams. Its the grown ups that need to understand that not all of them will.
The answer to some being unable is not to stop all from trying.
"Sorry, we no longer play football in the school because it'll make the kids who are no good at it feel bad".
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>> You think that's a waste of time and effort?
No, for many it's what's needed - though it should have a wider range of available subjects.
But the idea that every 15/16yo is suited to the study of five academic subjects to broadly O level equivalent is nonsense in most educationalists language. Failing some of the time is part of life. Failing all the time because the expectation is unrealistic is altogether different and accounts for a chunk of the disillusioned at 14 set that can be seen in any classroom.
That's not a particularly left wing point, nor does it owe anything to the 'no games so no losers' theory. There are members on the government side of the Commons who would prefer a strong element of vocational training alongside academic study.
What we're getting is another example of government in response to Mail headlines. There's little if any evidential basis for it.
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"There are members on the government side of the Commons who would prefer a strong element of vocational training alongside academic study. "
Yep - that's how it used to be 40 or 50 years ago with our polytechnics. Now every nincompoop has to have a degree in something or other.
Eventually the light will dawn on someone important, and we'll turn the clock back. Hooray!
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Let us know the answer when you get it.
Which will be mine. I'll bet a virtual wine gum on it.
I've googled it now. Appeal to authority. Solution U here:
www2.stetson.edu/~efriedma/published/fib/answers.html
So it's not just me.
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Well now, your link has thrown me because I had convinced myself otherwise. It seems pretty clear that a fibonacci number is the sum of the two immediately before it.
I can't find anything about putting skips in. Or any other manipulation for that matter.
But as you say, that reference certainly says that it is.
Last edited by: No FM2R on Mon 28 Sep 15 at 22:06
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I was going to say that I shouldn't have used the word Fibonnacci at the start, because it's just one of those typical sequences that are arbitrary but logical. And I too thought Fibonnacci didn't have skips. But my googled link uses the word Fibonnacci so I'm confused a bit too. And there are others there that do similar things.
I know Fibonnacci is spelled wrong in this post but it's auto corrected and damned if I'm fixing it on a crappy iPad.
Last edited by: Crankcase on Mon 28 Sep 15 at 22:16
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Never heard of Fibonnacci and I failed maths o level three times before giving up. So no idea wot the answer is. But after years in retail im good at mental sums.
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>> Never heard of Fibonnacci
>>
HTH
en.wikipedia.org/wiki/Fibonacci
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I cannot find a logic to any sequence which I can explain to No. 2, so she's going to admit defeat to her maths teacher tomorrow and obtain an explanation.
If the next number is 31 then you can have your wine gum and a grudging congratulations. But if its not I want a vodka in exchange for an explanation.
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"I cannot find a logic to any sequence which I can explain to No. 2"
Why not the straightforward explanation that I gave at 21:24? Even if it isn't the desired answer, your daughter will be seen as a wonderfully creative and imaginative thinker and given 9 out of 10. Maybe that's what the exercise is about.
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>> Next two numbers in the sequence?
>>
>> 4, 5, 9, 13, 22.....
>>
>>
31 & 53
Taking numbers in sequence order:
1+2=3
1+3=4
3+4=5
3+5=6 (9+22=31)
5+6=7(22+31=53)
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Although I'm reasonably good at numbers I've never liked this sort of problem. Especially since I've met the case where a sequence question is asked in an exam and there are two or more valid answers - just the person who set the problem can only see one. So you then have to decide what is the more likely one to have been picked as well. Urgh!
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True, I came up with:
1+2=3
1+3=4
3+4=5
3+5=6 (31)
5+6=7 (53)
Or,
1+2=3
(2+3)-1=4
3+4=5
(4+5)-1=6 (34)
5+6=7 (66)
Last edited by: gmac on Tue 29 Sep 15 at 09:24
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by inserting or removing things not required in the question (mangling it) you could invent any pattern to fit. Thats creativity, but not problem solving.
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"Thats creativity, but not problem solving."
It was creativity that solved the structure of DNA.
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>> "Thats creativity, but not problem solving."
>>
>> It was creativity that solved the structure of DNA.
I didn't say creativity was a bad thing. It does sometimes however invent nonsense.
Last edited by: Zero on Tue 29 Sep 15 at 09:51
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"by inserting or removing things"
Yeah I remember playing that game with a secretary and a kebab in Leytonstone.
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The Gmac and Cranks explanation is valid if we accept their addition of 1 and 3 to the beginning of the series. But I see no basis for it beyond convenience, and we can find a solution to most problems if we're allowed to make things up.
Beyond that I'm as stumped a parent as NoFM.
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As Zero and Will say, adding something not there to justify what you wan to put there is a bit iffy.
So this morning she'll take it to school with that problem not completed. And we'll see what the teacher has to say.
I'm still betting on an error in the text book.
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I should explain, the -1 is subtracting the number 1 from the sum of sequence numbers in the brackets.
We can only work with the information given and yes, assumptions have been made which as we all know is a bad thing. I'd still go with 31 and 53 and the simplest form of manipulation.
It is mathematics aimed at a 10 year old after all.
Last edited by: gmac on Tue 29 Sep 15 at 09:40
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I think it's an error. It occurs here in an article headed 'An assignment for school' alongside two correct examples.
prezi.com/zbbyub8xtw4u/the-fibonacci-sequence/
Someone has made a simple arithmetical error, published it without checking and it's been perpetuated by a teacher lifting homework tasks from the internet.
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By George he's right!
So
The answer is 35, 57
The method was to find the the source on the internet that you copied the question from, and looked up the next two numbers.
You can start a Fibonacci with any two numbers, as long as they aren't both 0, and put the largest first if you want - the ratio of one number to its predecessor will still tend to (1+5^0.5)/2.
Just don't ask me for the proof!
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Not necessarily an error - you're all hung up on a Fibonacci sequence - which it isn't, strictly. The sequence is A+B=C, A+C=D then repeat C+D=E, C+E=F. So it's a series of 2 operations rather than one - equally valid as a sequence, just not a Fibonacci!
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1. Without looking at the answers provided I could also spot a couple of the patterns people have included above.
2. Which is fair enough. But...
3. This means that there is not one unique solution.
4. Which makes it a great puzzle, as it teaches that you require external information in order to solve the problem. We'd never have won WW2 without the clever chaps at Bletchley doing puzzles like this. Which makes this statement by Zero:
"by inserting or removing things not required in the question (mangling it) you could invent any pattern to fit. Thats creativity, but not problem solving."
complete rubbish. It is exactly what problem solving is. It's what I enjoy from my day job. We have to achieve x. What about this? No, there's that problem. Well, what if we tweak that? No there's another problem. So what if we try this instead? Result!
Most likely, though, there's an error.
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" Which makes it a great puzzle"
All this talk of maths and creativity reminds me of an incident at school which I remember well to this day.....
The background is the A-stream at a grammar school; we were a reasonably bright lot and in maths we had been drilled into providing the working alongside the answers in our maths exercise books. Eventually, the maths teacher became fed-up with an excess of irrelevant stuff that was appearing and the 'working-out' was becoming bloated with a load of this unnecessary rubbish. "If I want waffle, I'll ask for waffle" he thundered " If I want waffle, I'll ask for an essay!!!"
Anyway, for the next evening's homework, he demanded waffle ....... and asked for an essay - a side and a half of foolscap on 'Triangles'.
I lacked any confidence in maths, and my imagination always struggled in essay-writing - how could I possibly stretch my knowledge of triangles into an essay? So, I wrote about the use of triangles in mechanics and construction - everything from my dad's runner bean frame to bridges and the construction of the Wellington bomber.
To my surprise, I got 9 / 10 marks while the rest of the class were getting 3, 4 or maybe a 5 for their waffle. But one of the girls got 10 / 10 ...... for a wonderful essay about a family of triangles which was later reproduced in the school magazine. It contained such gems as the baby, who was acute little fellow and his sibling that hadn't survived birth because his 3-sides didn't meet etc. I ended up at a poly while Gillian, IIRC, went to Oxford!
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>> "by inserting or removing things not required in the question (mangling it) you could invent
>> any pattern to fit. Thats creativity, but not problem solving."
>>
>> complete rubbish. It is exactly what problem solving is. It's what I enjoy from my
>> day job. We have to achieve x. What about this? No, there's that problem. Well,
>> what if we tweak that? No there's another problem. So what if we try this
>> instead? Result!
Result, is your clients go to jail because you create tax evasion. Your clients get vilified, Thats problem creation my old son.
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You believe too much of what Jeremy Corbyn tells you. It ain't like that! That sort of thing went out in the 1970s or 80s. Most of what was left in the 90s didn't make it into this millennium, and what did is now extinct.
It's all about avoiding inadvertent problems.
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What did the teacher say, NoFM?
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She's not home yet Haywain; on Tuesdays she has cookery lessons at the local Uni, so I doubt she'll be here before 6.30pm.
Having said that, I'm not sure she had Maths today, it may be that the next lesson is tomorrow.
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>> She's not home yet Haywain; on Tuesdays she has cookery lessons at the local Uni,
>> so I doubt she'll be here before 6.30pm.
>>
>> Having said that, I'm not sure she had Maths today, it may be that the
>> next lesson is tomorrow.
Who cares as long as she brings home some work from the cookery classes.
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>>she brings home some work from the cookery classes.
Mushroom ceviche
Guacamole
Steamed vegetables with a dip of Greek yogurt with coriander, mayonnaise and chives.
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It certainly did. Bless her little cotton socks.
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I had a little Fibonacci for my meal tonight, well I think that's what it was. Never heard of it before. It could be a problem though. I'll let you know around 05.30 tomorrow.
And as for the ruddy advert to my right, right now about VW Group Litigation....WTF. Asking if are you affected. Good lord, get a grip you eejits out there. If emissions were lower so likely would be the Torque. So cut the talk and just drive the *ocker.
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I went to cookery classes at Nottingham Technical College.
This was when it WAS a tech. coll. in the 1960s. They ran professional catering courses and after our own class we sampled the professionals' work for about a bob a nob.
Bargain (and I learnt how to cook a bit too, although my earliest foray was doing a Sunday lunch for the family when I was about 9 or 10!).
I did toy with becoming a chef, after leaving at school, but sense prevailed.(I think)!
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I cook with a frying pan and a barbecue.
But No. 2 likes cooking/preparing grown up stuff.
With one that likes hunting and another that likes cooking I am looking forward to a cheap old age.
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SWMBO was a Home Service Advisor with a couple of Gas Boards, mostly in Sheffield area, In the day, apart from demonstrating to thick people how to use new-fangled gas cookers (yes!) she did cookery demonstrations at Agri. shows, WIs etc and once shared a stage with Fanny Craddock - a vile woman so she tells me, but Johnny Craddock was a sweety!
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>>Home Service Advisor with a couple of Gas Boards,
My grandmother won second prize in a "Win a Ford Anglia" competition with the Gas Board from some show like this. Second prize was a Mrs Beeton - that has a label in the front cover describing it as this second prize. Mrs Beeton has, though, long outlasted the Anglia, no doubt.
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>> >>Home Service Advisor with a couple of Gas Boards,
>>
>> My grandmother won second prize in a "Win a Ford Anglia" competition with the Gas
>> Board from some show like this. Second prize was a Mrs Beeton - that has
>> a label in the front cover describing it as this second prize. Mrs Beeton has,
>> though, long outlasted the Anglia, no doubt.
I would guess the Anglia got more use.
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...I'm not sure she had Maths today, it may be that the next lesson is tomorrow. [Wednesday].
Well, what happened?
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Sorry, I found out last night and forgot to let you know.
The teacher initially said that x was the answer. Unfortunately No. 2 can't remember what x was.
No. 2 pointed out that didn't work so teacher considered, said that the problem was a mistake, and removed it from their homework.
A number of things about that don't make me happy so I will have.a chat.with the teacher later myself.
All a bit unsatisfying really.
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Oh well, thanks for reporting back.
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"so I will have.a chat.with the teacher later myself."
Pah! Just tell the teacher that your old mate Haywain solved it!
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10yr old Maths Homework - Haywain
