To convert inches to millimeters, what factor should you multiply the inches by?

To convert inches to millimeters, the correct multiplication factor is 25.4. This value is derived from the definition of an inch in relation to the millimeter. Specifically, one inch is exactly equal to 25.4 millimeters. Therefore, if you have a measurement in inches and you want to express it in millimeters, you multiply the number of inches by 25.4. This conversion factor is universally accepted in both scientific and engineering contexts, ensuring consistency and accuracy when converting between these two units of measurement.