Question

The ratio of copper and zinc in an alloy is 5:3. If the weight of the copper in the alloy is 30.5 grams, then the weight of zinc in the alloy is:

• A. 18.3 gm
• B. 20.6 gm
• C. 21.3 gm
• D. 22.4 gm

Hint:

For ratio problems, always divide the given amount by the total parts and then multiply by the required part to find the answer.

Answer 1

The Correct Option is A

Step 1: Define the total weight
Let the weight of copper be \( C \) and zinc be \( Z \). Given ratio: \[ C:Z = 5:3 \] Step 2: Find the proportion
Total parts = \( 5 + 3 = 8 \)
Total weight of the alloy: \[ \frac{30.5}{5} \times 8 = 48.8 \text{ gm} \] Weight of zinc: \[ Z = \frac{3}{8} \times 48.8 \] \[ = 18.3 \text{ gm} \] Thus, the correct answer is 18.3 gm.