A giant chocolate bar weighs \(16\,\text{oz}\).
a) Find the weight of one-eighth of the bar.
b) How much do three-eighths of the bar weigh?
c) A student says, “Two-eighths of the bar weigh the same as one-fourth of the bar.” Is the student correct? Support your answer with a calculation.
Hints
- How can you divide the total weight into eight equal parts?
- After finding the weight of one part, how can you find the weight of several parts?
- Calculate the two fractional weights separately, and then compare them.
Solution
1. Find one-eighth of the bar: \(\frac{1}{8} \times 16\,\text{oz} = 2\,\text{oz}\).
2. Find three-eighths of the bar: \(3 \times 2\,\text{oz} = 6\,\text{oz}\).
3. Two-eighths weigh \(2 \times 2\,\text{oz} = 4\,\text{oz}\). One-fourth weighs \(\frac{1}{4} \times 16\,\text{oz} = 4\,\text{oz}\).
4. Both fractions give the same weight, so the student is correct.
Answer
a) One-eighth weighs \(2\,\text{oz}\).
b) Three-eighths weigh \(6\,\text{oz}\).
c) Yes. Both two-eighths and one-fourth weigh \(4\,\text{oz}\).