# R5 | deepseek/deepseek-v4-pro | run 1

## Prompt

How many kilometers are in 100 miles? Show the conversion factor and cite a source for it.

## Response

100 miles equals exactly **160.9344 kilometers**. The conversion relies on the internationally agreed definition that 1 mile is precisely 1.609344 kilometers.

### Conversion Factor & Formula

The standard conversion factor is:
\[
\text{1 mile} = 1.609344 \text{ kilometers}
\]

This definition was established by an international agreement in 1959 and is maintained by standards bodies such as the National Institute of Standards and Technology (NIST). A mile is defined as exactly 1,609.344 meters, which yields the 1.609344 km factor when converted to kilometers [mileconverter.com](https://mileconverter.com/mile-to-kilometer/).

Applying the formula:
\[
\text{km} = \text{miles} \times 1.609344
\]
\[
100 \times 1.609344 = 160.9344 \text{ km}
\]

An equally valid method using the inverse factor (1 km = 0.6213711922 miles) arrives at the same result: \(100 \div 0.6213711922 \approx 160.9344 \text{ km}\) [unit-convert.com](https://unit-convert.com/length/miles-to-km.htm).

### Quick Reference

| Miles | Kilometers |
|-------|------------|
| 1 | 1.609344 |
| 10 | 16.09344 |
| 50 | 80.4672 |
| 100 | 160.9344 |
| 1,000 | 1,609.344 |

For practical purposes, 100 miles is often rounded to approximately **160.9 km**, but the exact conversion value is 160.9344 km [quickunitconverter.com](https://quickunitconverter.com/length/100-miles-to-km/).

Would you like to see how this conversion applies to a specific real-world distance, such as a race or road trip?
