How many calories are in a food that contains

.100 grams of CHO
. 20 grams of protein
. 20 grams of fat

What percentage of the total calories comes from:
. CHO
.Protein
.Fat

1 answer

All information that follows is based on FOOD calories (which really are kilocalories).
CH2O contains 4 cal/gram
protein contains 4 cal/gram
fat contains 9 cal/gram
so (100*4)+(20*4)+(20*9) = ?

%CH2O = [(100*4)/total]*100 = ?
same format for protein and fat.