Given,
640 calories from 8 apples.
We want to find out calorie content of EACH apple.
We want a UNIT RATIO in terms of APPLES.
So, we divide by number of apples.
We divide total number of calories given (for 8 apples) by total number of apples (which is 8).
Thus, we have:
640/8 = 80
Hence,
80 calories per apple
Correct Answer is A
