Final answer:
The brother ate 1/6th of the 72 grams of ice cream, which equals 12 grams. (Option B).
Step-by-step explanation:
To find out how many grams of ice cream the brother ate, you need to calculate 1/6 of 72 grams. Here is the step-by-step calculation:
- Divide the total amount of ice cream by 6 because the brother ate 1/6th of it. So, 72 ÷ 6 = 12.
- The brother ate 12 grams of ice cream.
Therefore, the correct answer is B. 12 grams.