Step 1: Start with the fraction 1/40.

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

1 ÷ 40 = 0.025

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

0.025 × 100 = 2.5%

Final Answer: 1/40 as a percentage is 2.5%.