how to calculate gpa for usa universities

Hello,
I am aspiring for a Mba programme from usa . My age 30 years
Work ex 4 years 2 months
Marks grad 75%
1st year 861/ 1200
2 nd year 945/1200
3rd yera 898/1200
4th yera 928/1200
12th 69%
628/900
10 th 71 %
355/500
Please Tell my gpa .do usa universities consider marks of 10th and 12th for calculating gpa for mba programme.

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