Step 1: Start with the fraction 90/80.

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

90 ÷ 80 = 1.125

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

1.125 × 100 = 112.5%

Final Answer: 90/80 as a percentage is 112.5%.