Mr M's OCR (not OCR MEI) Core 1 answers May 2012

I think i got between 59 and 62 out of 72, i.e. 82% - 86% do you think this is enough for an A

Nope
If only

Yeah I didn't either. Found it a bit odd considering there was a rationalising question in basically every past paper!

Looking at the past papers and their grade boundaries:
A B
Jan-07: 63 55
Jun-07: 60 52
Jan-08: 58 50
Jun-08: 63 55
Jan-09: 57 50
Jun-09: 58 51
Jan-10: 56 48
Jun-10: 58 50
Jan-11: 54 47
Jun-11: 61 54
Jan-12: 57 50

With the average for an A being 59 and B being 51. The grade boundary for an A has never exceeded 63, so I think this year, considering how straight forward the paper was; the A boundary should be in the region 60-63.

That's what my teacher was telling me today

oh, thank god. when i was going through the past papers and misinterpreted one of the rationalization questions, my thoughts were 'oh yeah, i thought it was weird i didn't rationalizse in that paper', good thing that doesn't apply here...



thanks for this! if i wanted to go for an A* for the two years, would an anticipated 70/72 compensate and allow me to get around 65 for C2?

Hi Mr M,

Thanks for posting these answers!
I got q. 6 wrong, but my method was mostly right, so how many marks would I drop?
I also got (20/3, -4) (forgot to divide by 2 to get the midpoints ) So how many marks would I get for that?

Also do you know what the raw marks usually are to get full ums on a C1 paper??

Do I loose anything for question 9ii) for leaving my answers as top heavy fractions? 14/10 instead of 1.4...

For question 4ii) If i completed the square incorectly could I still get the marks for the vertex anyone,thanks?

wasnt q9ii 20<7x+6<54 therfore x = 2 and 48/7? as it had a rectangle removed whereas 10x+6 was for the whole shape?

Ooh question 2ii as well. I forgot to complete it as 7^K

I just did (root7)/49... do I get a mark for that at least?

Hi Mr M
The only mistakes I see that I made was
9 i) i put -7<x<4

I mark dropped i guess?

10)iii) I left the length of the line as root 20 and didn't simplify but stated it was inside the circle. Will i drop a mark for not simplifying the surd.

also 9 ii) I left the answers in fractions in their simplest form, will i be penalized?

5)iii) is drawing the root sign only on the numerator but then not on the 5 going to drop a mark?

Thanks in advance

will i drop a mark for saying the discriminant is less than 0 for the last question but not stating what the discriminant is?

i did do some working out, but i left it in the form (number - larger number) under the sqrt sign in the quadratic equation

i also didn't consider x not being negative which brings me down 2 marks in total ):

Possibly none - all depends on how generous they feel.

In January i was 57/72 for an A and 50/72 for a B.

Do you think i will only drop 2 marks for using (10y + 3) and getting the range as 1.7<x<5.1, like many others have done?

i think i got 55≥x≥61 marks

Thanks for the answers, Mr.M.

For 9 ii), I completely misread the question and thought they were asking for the tile that had been removed. So I got my answer as 10/3 <= y <= 9. Would I get any marks for this or would my stupidity gain no marks (which would be understandable).

For question 10 (iii) did you have to give the answer in simplified surd form, or was stating that 'Root(20)<Root(25) therefore P is in circle' be sufficient?