Normally an A, but it depends on the grading scale of the school.
a
90 percent is around B and A on a test.
86% to 90% is a B plus.
90 percent is an a ofc. Like and A cannot be a B C or D because they are way too low.
If b = 9 then the value of 10b is 90
It depends on the grading scale but most of the time is a low "B" Common grade scale by percent 100-90=A 89-80=B 79-70=C 69-60=D 59 and below=F
This will normally be a grade of B.
B- 100- 90 a+ - a- 89-70 b+ - b- 69-60 c+ - c- 59-50 d+ - d- 49-0 f - f
81% or B-
In grade form that would equate to a B, maybe a B+ to some.
Most scales have it at a B- Check to see which scale applies to you.
Grade scale 100-90=A 89-80=B 79-70=C 69-60=D 59-0=F So a 64 is a D
B.