Maths question help please

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tmacka
Posts: 2
Joined: Thu Jul 23, 2015 4:16 pm

Maths question help please

Post by tmacka »

Can anyone help with this please - is there a formula that makes this easy to work out? The question is:
Rangers and Celtic are playing a football math. There are 5 goals scored at the end and Rangers win. How many different half time scores are the?

Thanks for any advice
Guest55
Posts: 16254
Joined: Mon Feb 12, 2007 2:21 pm

Re: Maths question help please

Post by Guest55 »

You are better working logically than trying to remember a formula.
mystery
Posts: 8927
Joined: Tue Jul 21, 2009 10:56 pm

Re: Maths question help please

Post by mystery »

Thinking aloud. At the end the scores can be 5 0, 4 1, 3 2

So part way through the game, if end score was 5 0 possibilities are 0 0 , 1 0, 2 0, 3 0, 4 0

If end score was 4 1, part way through the possibilities could end with a 1 or a 0 ..... so quite a few to work through

If end score was 3 3 score could end with a 3 2 1 or 0 so even more to work through.

I suppose something a bit like a decision tree might help a child set out all the different possibilities logically?

It's getting a child to the point where they can think through all the possibilities logically and set them out that is the tricky thing here ...... to have a method which covers all the options rather than them just stabbing in the dark at a few of the options.

It's a good question. It's the kind of thing my daughter needs practice with. She'd get upset because it was football and say she knew nothing about football.
yoyo123
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Joined: Mon Jun 18, 2007 3:32 pm
Location: East Kent

Re: Maths question help please

Post by yoyo123 »

Diagrams and/or jottings really help too.
tmacka
Posts: 2
Joined: Thu Jul 23, 2015 4:16 pm

Re: Maths question help please

Post by tmacka »

Yes - thanks - logical workings are the way my son did it, however I'm really wondering if there is a formula to work out this type of problem? I wonder if anyone could suggest one please?
Thanks
russet
Posts: 243
Joined: Sat Aug 10, 2013 12:46 pm

Re: Maths question help please

Post by russet »

Imagine the other team scored 0. Rangers could have scored 0,1,2,3,4, or5.
Imagine the other team scored 1. Rangers could have scored 0,1,2,3 or 4,
Imagine the other team scored 2. Rangers could have scored 0,1,2 or 3
The other team could not have scored 3, or they would have won.
So you are adding 6+5+4.
This is a section from triangular numbers. Triangular numbers just mean:
1,
1+2,
1+2+3
and so on until you get to in this case 1+2+3+4+5+6.
So you could use the formula for adding triangular numbers to 6 then use the formula again to subtract the triangular numbers to 3.
This is a long winded way of saying: yes, there is a formula, but in this case it is more trouble than it is worth and way beyond 11+.
(The formula for triangular numbers is n(n+1)/2, where n is the number of numbers you are adding)
Guest55
Posts: 16254
Joined: Mon Feb 12, 2007 2:21 pm

Re: Maths question help please

Post by Guest55 »

Some teachers call them triangle numbers as they make a triangle

*
**
***
****
*****

They crop up in lots of problems as they form part of Pascal's triangle.
Rads2005
Posts: 36
Joined: Wed Nov 12, 2014 4:49 pm

Re: Maths question help please

Post by Rads2005 »

Hi

Can we know the correct Answer ?

Thx
Guest55
Posts: 16254
Joined: Mon Feb 12, 2007 2:21 pm

Re: Maths question help please

Post by Guest55 »

The answer is in russet's post!
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