1 3/5- 6,8=

To solve \(1 \frac{3}{5} - 6.8\), we first convert \(1 \frac{3}{5}\) to an improper fraction.

1. Convert \(1 \frac{3}{5}\) to an improper fraction: \[ 1 \frac{3}{5} = \frac{5 \times 1 + 3}{5} = \frac{5 + 3}{5} = \frac{8}{5} \]

2. Now, we need to express \(6.8\) as a fraction: \[ 6.8 = \frac{68}{10} = \frac{34}{5} \quad \text{(after simplifying)} \]

3. Now we can rewrite the original problem with both terms as fractions: \[ \frac{8}{5} - \frac{34}{5} \]

4. Since the denominators are the same, we can subtract the numerators: \[ \frac{8 - 34}{5} = \frac{-26}{5} \]

5. Finally, we can convert \(\frac{-26}{5}\) back to a mixed number if desired: \[ -26 \div 5 = -5 \quad \text{(with a remainder of 1)} \] Thus, \(\frac{-26}{5} = -5 \frac{1}{5}\).

So, the answer is: \[ 1 \frac{3}{5} - 6.8 = -5 \frac{1}{5} \text{ or } \frac{-26}{5} \]