1 oz = 28.3 grams
1 oz of 75/25 ground beef is 75% by weight lean beef and 25% by weight fat OR: 21 grams of meat to 7 grams of fat.
"Meat" isn't just protein; it also contains water. That's why when you cook it, it turns brown and shrinks - the water comes out.
1 oz of 75/25 (by weight) ground beef has 4 grams of protein and 7 grams of fat which is 11 grams total. The rest is water, maybe some connective tissue.
4 grams of protein is 16 calories. 7 grams of fat is 63 calories. For a total of 79 calories (the nutritional info states 82 calories, so there's a fraction in one of the categories not accounted for because of rounding).
7 grams of fat is indeed 25% of an ounce by weight.
63/82 = % calories that are fat ~ 77% of calories from fat.
Hope that helps.
I rarely eat fattier than 90/10 and always stock up on 95/5 when at Whole Foods. But some folks don't like burgers that are leaner than 85/15 or 80/20.
"Right is right, even if no one is doing it; wrong is wrong, even if everyone is doing it." - St. Augustine