Freshman year: 2.1 GPA
Sophomore year: 1.9 GPA
Junior year: 3.1 GPA
Senior year: 3.5 GPA
Total grade points: 2.1 + 1.9 + 3.1 + 3.5 = 10.6
Total credits: 4 years = 120 credits
GPA = Total grade points / Total credits
GPA = 10.6 / 120 = 2.53
Therefore, your GPA is 2.53.