18 carat gold contains

Options

A. `60%` gold
B. `75%` gold
C. `18%` gold
D. `60%` gold

Explanation

To solve the question regarding the composition of 18 carat gold, we need to understand what "carat" means in the context of gold purity.

### Step-by-Step Solution:

1. **Understanding Carat System**:
- The carat system is a way to measure the purity of gold. Pure gold is defined as 24 carats. This means that 24 carats is 100% gold.

2. **Calculating the Gold Content in 18 Carat Gold**:
- To find out how much pure gold is in 18 carat gold, we use the formula:
\[ \text{Gold content} = \left( \frac{\text{Carats of gold}}{24} \right) \times 100 \]
- For 18 carat gold:
\[ \text{Gold content} = \left( \frac{18}{24} \right) \times 100 \]

3. **Performing the Calculation**:
- First, calculate \( \frac{18}{24} \):
\[ \frac{18}{24} = 0.75 \]
- Now, multiply by 100 to find the percentage:
\[ 0.75 \times 100 = 75\% \]

4. **Determining Other Metal Content**:
- Since gold is 75% of the alloy, the remaining percentage will be other metals (like copper, silver, etc.):
\[ \text{Other metals} = 100\% - 75\% = 25\% \]

### Final Answer:
18 carat gold contains 75% gold and 25% other metals.