how do i calculate an unweighted gpa?

<p>my school does it gpa's on weird kind of scale(4.0 for a 100 in a normal class, 5.0 for a 100 in an honors class, and 6.0 for AP or pre-AP classes). My gpa is 4.2 (weighted, i think). I could really use some help</p>

<p>Here's a fairly common one...</p>

<p>A+ (97-100) = 4.0
A (93-96) = 4.0
A- (90-92) = 3.7</p>

<p>B+ (87-89) = 3.3
B (83-86) = 3.0
B- (80-82) = 2.7</p>

<p>C+ (77-79) = 2.3
C (73-76) = 2.0
C- (70-72) = 1.7</p>

<p>D+ (67-69) = 1.3
D (65-66) = 1.0
E/F (below 65) = 0.0</p>

<p>Treat them all like normal classes - no extra points for honors or AP.</p>

<p>Collegeboard's site has info on converting your GPA to a 4.0 scale.</p>

<p>A = 4
A- = 3.7
B+ = 3.3
B = 3
B- = 2.7</p>

<p>etc</p>