Ratio problem
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Ratio problem
If one cake and two biscuits provide 450 calories and two
cakes and three biscuits provide 800 calories, how many
calories are provided by one biscuit?
How to solve this problem, please?
cakes and three biscuits provide 800 calories, how many
calories are provided by one biscuit?
How to solve this problem, please?
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Re: Ratio problem
How old is the child tackling the problem? I know how I'd do it but it might not be appropriate for someone in say, year 5.
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- Posts: 1763
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Re: Ratio problem
In which case I'll leave it to the maths teachers on here because I may end up confusing the situation. I suspect my method won't have been covered in school yet.
Re: Ratio problem
Hi Erijhkan - Is this for an 11+?
Anyway, can you work out how many calories there are in 1 cake and 1 biscuit? Hint: look at the difference between the facts you have been given.
From there you can compare 1 cake and 1 biscuit with 1 cake and 2 biscuits. The difference will be the extra biscuit.
Edit: Crossed post with anotherdad. I suspect this is beyond KS2. Guest will know for sure.
Anyway, can you work out how many calories there are in 1 cake and 1 biscuit? Hint: look at the difference between the facts you have been given.
From there you can compare 1 cake and 1 biscuit with 1 cake and 2 biscuits. The difference will be the extra biscuit.
Edit: Crossed post with anotherdad. I suspect this is beyond KS2. Guest will know for sure.
Re: Ratio problem
Thanks for your reply. it is helpful.
Yes, this is for 11+, from one of the grammar school paper.
Yes, this is for 11+, from one of the grammar school paper.
Re: Ratio problem
This is not a Year 5 question.Erijkhan wrote:If one cake and two biscuits provide 450 calories and two cakes and three biscuits provide 800 calories, how many calories are provided by one biscuit?
one cake and two biscuits provide 450 calories
two cakes and three biscuits provide 800 calories
The difference between these two sentences tells us that one cake and one biscuit provide 350 calories.
Now compare to the first sentence - the 'extra' biscuit must be 100 calories.
{It is not appropriate to try and use algebra for these}
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Re: Ratio problem
you know:Erijkhan wrote:If one cake and two biscuits provide 450 calories and two
cakes and three biscuits provide 800 calories, how many
calories are provided by one biscuit?
How to solve this problem, please?
1c + 2b = 450
2c + 3b = 800
therefore, from the first fact
2c + 4b = 900 (by doubling)
therefore the diff is 1b so 1b = 100
Re: Ratio problem
Reading mum - algebra is not appropriate or needed here.
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- Posts: 1841
- Joined: Tue Oct 04, 2011 9:44 am
- Location: Reading
Re: Ratio problem
its the only way I know, and how my DD would have done it (probably related to the first point)