Hi if you have a 65% grade can a 80% bring it up to a C 70%

Not a 70%, but a 72.5% (or a 73%)

Step-by-step explanation:

Assuming that the 65% is the first grade and the 80% is your second, adding both numbers and dividing by 2 will get you 72.5%.

The best possible grade you can get from that 65% is an 82.5%, or 83% if you round the grade up. 100+65=165÷2 will get you 82.5.

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step-by-step explanation:

the solution is in the picture