Suppose that a student at some university somewhere and gets the report card: What is their grade point average?

class	credit	grade
MATH 181	4	B-
ENGL 121	5	C
BIOL 105	4	B+
PYCH 101	5	A
CHEM 131	4	A-

Also suppose that the catalog says the grades points are as follows:

Letter Grade	Grade Points Earned
A	4.0
A-	3.7
B+	3.3
B	3.0
B-	2.7
C+	2.3
C	2.0
D	1.0
F	0.0