What per cent of 90 is 18 ?

Answer

To solve the question "What percent of 90 is 18?", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: We need to find out what percentage \( x \) of 90 equals 18. This can be expressed mathematically as:
\[ x\% \text{ of } 90 = 18 \]

2. **Convert Percentage to Fraction**: We can convert \( x\% \) into a fraction:
\[ \frac{x}{100} \times 90 = 18 \]

3. **Set Up the Equation**: Now, we can write the equation based on the above expression:
\[ \frac{x}{100} \times 90 = 18 \]

4. **Multiply Both Sides by 100**: To eliminate the fraction, we can multiply both sides of the equation by 100:
\[ x \times 90 = 18 \times 100 \]

5. **Calculate the Right Side**: Now, calculate \( 18 \times 100 \):
\[ x \times 90 = 1800 \]

6. **Isolate \( x \)**: Next, we need to isolate \( x \) by dividing both sides by 90:
\[ x = \frac{1800}{90} \]

7. **Perform the Division**: Now, perform the division:
\[ x = 20 \]

8. **Conclusion**: Therefore, \( x = 20 \), which means:
\[ 20\% \text{ of } 90 \text{ is } 18 \]

### Final Answer:
The answer is **20%**.

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