Step 1: Start with the fraction 45/15.

Step 2: To convert a fraction into a percentage, divide the numerator by the denominator.

45 ÷ 15 = 3.0

Step 3: Multiply the result by 100 to get the percentage.

3.0 × 100 = 300.0%

Final Answer: 45/15 as a percentage is 300.0%.