One of the supplied ingredients will have a left over. 300mL of lime being 5 parts means one part is 60mL (300/5). To make up the fiz to the recipe would therefore need 3* 60 = 180 mL of lemonade, so the lemonade is in excess, and he can make 300 + 180 = 480 mL of fiz.

In these straitened times in reality I'd just bung in all the lemonade, don't waste it!

The simple intuitive method of calculation:

Every 8ml of product require 5ml of lime and 3ml of lemonade

300ml lime would make 300/5 lots of 8ml = 60

200ml of lemonade would make 200/3 lot of 8ml = 66 2/3 lots of 8ml

Clearly there is insufficient lime to make 66 2/3 lots of 8ml, so the answer is 60 lots of 8ml = 480ml

Materials totalled 500ml, so 500ml-480ml = 20ml (of lemonade) left over.

In reality, just mix the whole lot together and the error in ratios is not that great🙂. Not many would notice the difference!

Paul should have said "to hell with lemonade where's the soothing real ale?"

Strictly speaking he can make 500ml of fizzy drink. 480ml of lime/lemonade mix and 20ml of straight lemonade.

Top marks.

 Another defining attribute is he THINKS he has . ????

Steve.

Edited By Steviegtr on 15/04/2020 23:30:20

Nah. It takes 50 years to turn school students imbued with the required native common sense into pedantic nitpickers with the spare time to sit around and split such hairs. (And mix such metaphors!).

The advent of precise single pan weighing devices has complicated cooking recipes to an extent. In the days of old the other ingredients would likely be balanced against the number of eggs on the other pan. Simple ratios, so the cake, or whatever, came out sized according to small or large eggs, not precise weights of every ingredient. Such is progress🙂.

There were never any ‘part eggs’ left over and the product would be just as consistent from one session to another – apart from the slightly different size – as those made by more modern equipment.

On the plus side for these days, all the ingredients can be added to the mixing bowl, tared on the weighing device so people who can not do maths can at least simply follow the weights quoted in the recipe.

There you are guys, be careful of asking questions like this when there are ex-accountants lurking around.

That is half the trouble with accountants. They would look to save that 20ml of lemonade for another day!

And it would likely actually cost more, in time and resources, to measure out that 180ml than pouring in the full 200!🙂

Which is the odd one out of 'banana, lemon, and orange'? [edited so it works better…]

The answere is, of course, 'and'. (Thanks to the film 'Funny Bones' for that…)

Seriously, what age of pupil was this question aimed at? And what is the typical age of this thread's participants? No wonder thread-cutting gear train problems still keep coming up…

However, the OP asks a valid question about explanation of the method; he's not asking what the answer is. Having tried to teach/explain a few mathematically-based things to graduates – and failed abysmally – I have great respect for good maths teachers. Unfortunately, they seem to be few and far between. I was lucky, but, of course, didn't know it at the time.

Edited By Kiwi Bloke on 16/04/2020 08:36:47

That was an entrance exam question for prep school. I'd guess I was about 9 or 10yrs old The only question that threw me was 'What are baby rabbits called'

I knew baby hares were leverets but i'd not heard the term kittens for young rabbits back then and it haunted me for years…

I ws probably a little sh!t back then. At least I've got bigger…..

pgk

Isn't assuming the question is about the example a classic 'common sense' mistake?

Surely unlikely in practice that a maths question featuring ratios is actually about making Lemonade. Or that the examiner will reward a joke. No. Exams seek to sort the wheat from the chaff. You're chaff if you can't do the sum, and you're chaff if you don't understand the point of the question!

Smart-a**e answers to maths questions only get applauded in pubs and on internet forums. Elsewhere, you is toast! Don't ask how I know…

Dave

Sadly as someone who has marked public examinations for over 25 years, answers of these types do happen, either because the candidate doesn't know they are being smart, or often when it appears they have no interest in completing the exam in a sensible fashion.

it would be unprofessional to give any actual examples from public exams, except to say that every exam board has a procedure in place for abusive, unacceptable and offensive responses as well as to deal with any disclosures made of criminal activity.