In most places it isn't possible. In the article Sincerity Annabelle linked both those students are in Hillsborough County FL schools and apparently weighting the college classes much higher than high school classes. I live in FL as well, but on the other side of the state. We have the same program where you can graduate high and community college with an associates degree, but that GPA's are not weighted in such a way. The highest GPA they can have is a 5.0
Actually its dependent on how they're grading you. That 4.96 could be out of a 10.0 GPA and would be horrible or it could be out a 5.0 and would be very good.
First convert your 10 scale to a percentage: 7/10 = .7 = 70%
Then calculate 70% of 4.0: 4*.7 = 2.80
letter grade would be C+
On a direct percentage:grade conversion - 70% is usually a C and a C is a 2.0; but that method is used to assign single grades more than it is used to assign an average.
The only accurate way to calculate your GPA on a 4.0 scale is to recalculate it based on each course grade converted to 4.0 instead of 10.
Here are online GPA Calculator through which you can do various calculations : https://calculator-online.net/cgpa-calculator/