It seems you have provided a series of ratios or fractions. However, the format appears a bit unclear, and some parts seem to be for spacing or HTML entity entities (like ` ` for non-breaking spaces).

Here's a breakdown of what you have:

1. **800:125**
2. **800:125**
3. **715:25**
4. **66:0.55**
5. **12:3.4**

If you would like to calculate these ratios or need them to be simplified, please clarify your request. For example, I can simplify these ratios or perform operations on them if needed.