Habs question help

11 Plus Maths – Preparation and Information

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muksoni
Posts: 14
Joined: Sun Oct 31, 2010 8:43 am

Habs question help

Post by muksoni »

Following is the question from Habs 2010 paper.

Four friends, Alwyn, Bax, Coates and Delius have lunch together. Although each eats a differently priced snack, they share the bill equally. Yesterday, this resulted in Alwyn paying £1 less than the cost of his snack, Bax paying £3 more, Coates £4 less and Delius paid £4. What was the actual price of the snack that each friend ordered?

Alwyn: ________

Bax: ________

Coates: _______

Delius: _______

I know we can make 3 equations with 3 variables and substitute variables in equations to get the answer, but is there any more simple way of solving the same?
hermanmunster
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Location: The Seaside

Re: Habs question help

Post by hermanmunster »

muksoni wrote:Following is the question from Habs 2010 paper.

Four friends, Alwyn, Bax, Coates and Delius have lunch together. Although each eats a differently priced snack, they share the bill equally. Yesterday, this resulted in Alwyn paying £1 less than the cost of his snack, Bax paying £3 more, Coates £4 less and Delius paid £4. What was the actual price of the snack that each friend ordered?

Alwyn: ________

Bax: ________

Coates: _______

Delius: _______

I know we can make 3 equations with 3 variables and substitute variables in equations to get the answer, but is there any more simple way of solving the same?
This on is fairly easy as we know they paid £4 each so total = £16. So D's snack was £4, C's = £8 A's=£5 and B's £1 - no need for anything too complex.
muksoni
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Joined: Sun Oct 31, 2010 8:43 am

Re: Habs question help

Post by muksoni »

Thanks. I knew i was missing some simple trick.
vasu
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Re: Habs question help

Post by vasu »

Its just my logic, but I think there is one correction to cost of D's snack :
We know the total = £16.
The answers though, do not add to 16 :
D's snack was £4, C's = £8 A's=£5 and B's £1 => Making the total as 18.
A way to work this out probably is :
A-1=4, B+3=4, C-4=4, D=4
A=5, B=1, C=8 : All these snacks add to 14. So the last snack for D must be 2, making the total bill as 16.
Hence D's snack = 2
Snack costs => A = 5, B = 1, C = 8, D = 2
I think it looks right, but I hope I got this correct....
Having one child makes you a parent; having two you are a referee.
hermanmunster
Posts: 12815
Joined: Fri Sep 15, 2006 9:51 am
Location: The Seaside

Re: Habs question help

Post by hermanmunster »

on beach
brain addled
will look again later... am sure we have looked at this one before....
Viral
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Re: Habs question help

Post by Viral »

The question has effectively told us each person paid £4.

So all we have to do is take £4 and work out their 'fair share' based on the info already given.

A paid £4 and has underpaid by £1 => A should have paid £5.
B paid £4 and has overpaid by £3 => B should have paid £1.
C paid £4 and has underpaid by £4 => C should have paid £8.
The real total was £16 and the others should have paid £14 (£5 + £1 + £8). So D should have paid £2.

That's prob how I would explain it to my kid.

PS I went to Habs - seems they have hardly changed the 11+ maths exam since I did it in 1998!
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