GCSE Maths question, please help!

stamina9008

Right, i just completed my homework and got 80%..
This was out of 12 questions, and i only got one wrong...
So, that would mean that i should have got 92%, right?
The only reason i would think that i got 80% is because my tutor said that i didnt cancel down my fractions for the Probability homework.
The reason i didnt is because im using a revision aid/tool called 'Mathswatch', its a CD tutorial thing, and in it the lady said that you DO NOT have to cancel down fractions when doing PROBABILITY.
So, im saying, should i raise this with my tutor and question her marking, or leave it?
Please, someone tell me, who is right....my in class teacher, or the tutor on the Mathwatch CD????????

Thanks

Stooby2

Depends on what your teacher has told you before and what was expected of you. You can try arguing the matter with your teacher and explain what was said on the CD, but at the end of the day, does it really matter for some homework? I'd understand if this was a GCSE or a mock or something important.

Handsome90

I was always taught to cancel fractions to the lowest form during probability. For example, my tutor taught me to cancel down 4/8 to 1/2. Strictly speaking, I don't think GCSE maths examiner would deduct marks for not cancelling down fractions. But that's just my opinion.

[Deleted User]

Well.. from A Level maths you always present probabilities as decimals.. But I would expect any 'final result' that involved a fraction to show it in it's lowest possible form

miduck

Handsome90 wrote: »

I was always taught to cancel fractions to the lowest form during probability. For example, my tutor taught me to cancel down 4/8 to 1/2. Strictly speaking, I don't think GCSE maths examiner would deduct marks for not cancelling down fractions. But that's just my opinion.

I can't speak for now but they certainly used to - it would be stated in the marking scheme.

malcumms7898

It isn't necessary, because (as the above example stated) 4/8 and 1/2 are the same thing, they are just different ways of writing the same thing. Although if it is how your teacher/examiner expects you to do it then it is probably a good idea to get into the habit of doing it. You wouldn't offer somebody 4 eighths of your cake, you would offer them half. It makes sense to express it in the most simple form. Your tutor probably has a better idea of what is expected of you on your exam than the Mathswatch CD.

Lum

If the exam boards say you need to do that to get full marks, then you need to do it even if it does seem pointless.

As well as teaching you maths, your teacher is teaching you how to pass the exam, listen to them. At the end of the day this result is just feedback so that you know not to make the same mistake in the exam.

misiek404

malcumms7898 wrote: »

It isn't necessary, because (as the above example stated) 4/8 and 1/2 are the same thing, they are just different ways of writing the same thing..

My thoughts exactly. From mathematical point of view it is the same thing and that is all that matters. If your teacher deducts marks for this, she either thinks you can't simplify or she is an idiot.

johnnyboyrebel

misiek404 wrote: »

My thoughts exactly. From mathematical point of view it is the same thing and that is all that matters. If your teacher deducts marks for this, she either thinks you can't simplify or she is an idiot.

Or (as is more obviously clear) the teacher is making a point of hghlighting the fact you didn't reduce down so you follow good practice in the future.

'She is an idiot' is a highly intelligent response..

spud17

DO NOT have to cancel down fractions when doing PROBABILITY

If the question was related to probability, then I'd be reluctant to change 100/8 to 25/2.

For fractions they are the same, but not for probability.

Think betting odds.