How do you calculate a weighted grade into a percentage?

For example, 64.97 / 75

86%

Step-by-step explanation:

64.97 / 75 = 0.8662 ...

0.8662 x 100 = 86%

but it weighted so:

0.8662 x actual weighted % = % got out of weighted %

example:

Test is Weighted 25% out of 100%

0.8662 x 25% = 21 %

this case you got 21% out of 25% for the test