I have been spending days trying to work the UMS marking system to calculate what i could achieve after exam. I am sharing with others who might not get it how it all works.

GCSE
you need:
90% of the UMS marks to get an A*
80% for A
70% for B
60% for C
50% for D
40% for E

all you need to find out is how much UMS are needed in the GCSE
for example, OCR triple science: each subject is worth 300 marks.

Now using weighted average mean
you calculate what each of the exams and courseworks are worth.
My example - physics coursework is worth 33.3% of the course, therefore 0.33 x 300= 99, round to 100
two of the three exam are worth 16.6%, so 0.16 x 300= around 50. Each exam is worth around 50 UMS marks
and the final exam is work 100 marks

I want an A*, i have 41/ 50 in one exam=A, i have 46/50 in exam two=A*
so i need at least 92/100 in my course work and final exam to get that.

you need 270 marks for an A*
240 for an A
210 for a B
180 for a C
etc.

The same method can work for any amount of UMS marks as long as you know the percentages, so you know what you need for each subject and you can use any previous results for work out what you need to get for your predicted grades.