how can i make the content equal the same %? what did i do wrong?

Question

Lunch: Ground nut protein

Fat content = 3.5 grams
1 gram contains fat of 9 calories
2 grams contain fat of 9 x 3.5 = 31.5 calories
Total quantity = 320 calories
Fat content = (31.5/320) x 100 = 9.84%

Protein content = 8 g
1 gram contains protein of 4 calories
8 grams contain protein of 8x4 = 32 calories
Total quantity = 320 calories
Protein content = (32/360) x 100 = 8.89%