Question

I got 97.27 from 25% exam and on the project I got 97 and it is 25% and on the practical got 93.33 from 20%.

Answer 1

Contribution of the exam score to your ultimate grade: $0.25\cdot97.27\approx24.32$

Contribution of the project: $0.25\cdot97=24.25$

Contribution of the practical: $0.20\cdot93.33\approx18.67$

Contribution of the final exam: $0.30x=y$, where $x$ is the score you get on the final exam and $y$ is the percentage that score contributes to your grade.

You want to end up with an A, a minimum grade of 90%, so

$24.32+24.25+18.67+y=90\implies y=22.76$

Then the minimum score you need to get on the exam is

$0.30x=22.76\implies x=\dfrac{22.76}{0.30}\approx75.87$