Step 1: Start with the fraction 42/3.

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

42 ÷ 3 = 14.0

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

14.0 × 100 = 1400.0%

Final Answer: 42/3 as a percentage is 1400.0%.