LLB Final grade?

I’m a final year law student. My degree is weighed 33% of year 2 and 66% of year 3. There is a 5% synoptic added to each module this year (3 modules).
My average for second year was 50%. This year, the first set of assessments weighed 40%. In the first set, I scored 72, 52 and 48.
How much do I need in the second set of assessments, after the 5% synoptic, in order to get a 2:1 overall?

(I’ve tried calculating so many times but got a few different answers)

You say that there are three modules this year; are they equally weighted?
Are the three assessments which you have completed so far for each of the three separate modules? So one assessment per modules done already, and one assessment (plus the synoptic) still to do?
You say that the first set of assessments are weighted at 40%. Would I be correct in assuming that the second set of assessments are weighted at 55%? So each module has a 40% assessment, a 55% assessment and a 5% synoptic?

Second set are 50% and then a 5% synoptic is added

Er, you said "the first set of assessments weighed 40%" and now you've said that the "Second set are 50% and then a 5% synoptic is added". That's only 95%. Where's the other 5% gone?
Also, I asked three questions above. You answered just one of them. I'll try again with the other two.
1. Are all modules this year treated equally? (For example, are they all worth 40 credits?)
2. For which modules are your 72, 52 and 48 marks this year? Is each one of these for a separate module? Or are the 72 and the 52 for one module, and the 48 for another module, with no assessments yet for the third module? (Every university, and every course, does this differently - and I'm keen not to make any assumptions as to how your course works.)

Oh sorry. In the second set, one module is worth 55%, the other 2 are worth 50%.

With the total being 95%, there is a 5% synoptic which is added separately.

Yes all 3 modules are 40 credits. The 72, 52 and 48 are each from a separate module, criminal procedure, family law and human rights law.

There’s now a second assessment for the same modules. The family law module is weighed differently. For family law, the first assessment is weighed at 55% and the second is weighed at 40% and then a 5% synoptic will be added.
For criminal procedure and human rights, the first assessment was 45% and the second will be 50% and then a 5% synoptic will be added.

Excellent, the numbers tally now.
Your overall degree is 1/3 of your weighted average year 2 mark (which was 50%) plus 2/3 of your weighted average year 3 mark. You want 60% overall for a 2:1, so you need a weighted average in year 3 of 65% (because 1/3 of 50% + 2/3 of 65% is 60%). So, 65% is our year 3 target.
I'm going to use the abbreviations CP, FL and HR to refer to Criminal Procedure, Family Law and Human Rights respectively. I'm going to use the suffix a1 for assessment 1, a2 for assessment 2 and s for synoptic.
Your weighted average year 3 mark is: ((45% of CPa1 + 50% of CPa2 + 5% of CPs) + (55% of FLa1 + 40% of FLa2 + 5% of FLs) + (45% of HRa1 + 50% of HRa2 + 5% of HRs)) / 3
To make things easier, I'm going to give you the same target for each outstanding assessment / synoptic - i.e. I'm going to consider CPa2, CPs, FLa2, FLs, HRa2 and HRs to be equal to each other. I'm going to call that value X. We can therefore simplify the above, insert the known values for CPa1, FLa1 and HRa1, and set the result to be 65 - our year 3 target - as follows:
((45% of 72 + 50% of X + 5% of X) + (55% of 52 + 40% of X + 5% of X) + (45% of 58 + 50% of X + 5% of X)) / 3 = 65
We can solve for X (or just use Goal Seek in Excel!) to establish that X must be 73. So 73% is your target for each remaining assessment and synoptic.
We can plug that into the above to check:
((45% of 72 + 50% of 73 + 5% of 73) + (55% of 52 + 40% of 73 + 5% of 73) + (45% of 48 + 50% of 73 + 5% of 73)) / 3 = 65.25%
We already know from the above that you need 65% this year to get 60% overall. So it all works out: 73% is your target for everything yet to come.

Thank you so so much! This really helps and makes this a lot more clearer, thank youuu!!

You're welcome.

Sorry to bother you again. The 73% that I need, is that after the synoptic?
I’m really sorry but I just realised I forgot to mention the synoptic is just a project we have to submit and submitting that project would add 5% to our grades in each subject. The synoptic doesn’t really have a mark as such.
Would I still need 73%?

So sorry, I totally forgot to mention this earlier

If the synoptic doesn't have a mark, is it just a pass/fail? And if you pass you get the whole 5% added to your grade?

Yes it’s just pass/fail and yes if you pass, it’s the whole 5% added to each the grade for the 3 modules