The problem asks to convert the percentage $90\%$ into a fraction.

1. Problem Description

The problem asks to convert the percentage $90\%$ into a fraction.

2. Solution Steps

To convert a percentage to a fraction, we divide the percentage by 100 and simplify the fraction.

$90\% = \frac{90}{100}$

Now, we simplify the fraction by dividing both the numerator and the denominator by their greatest common divisor, which is

1

0. $\frac{90}{100} = \frac{90 \div 10}{100 \div 10} = \frac{9}{10}$

The fraction $\frac{9}{10}$ is in its simplest form.

3. Final Answer

The fraction is $\frac{9}{10}$.