Convert Decimal to Fraction: Writing 1.3 as a Proper Fraction

To solve this problem, we will convert the decimal $1.3$ into a fraction.

Step 1: Identify the whole number and decimal component. The number $1.3$ consists of the whole number $1$ and the decimal $0.3$.

Step 2: Convert the decimal $0.3$ to a fraction. The decimal $0.3$ means three-tenths, which is expressed as the fraction $\frac{3}{10}$.

Step 3: Combine the whole number and the fractional part into a mixed number. The number $0.3$ is converted to $\frac{3}{10}$, and adding the whole number $1$ gives us the mixed number $1 \frac{3}{10}$.

Therefore, when the decimal $1.3$ is expressed as a fraction, it is written as $1 \frac{3}{10}$.