You should reduce speed by ___ to ___ percent when driving in adverse weather conditions.

When driving in adverse weather conditions, such as rain, snow, or fog, it's crucial to reduce your speed significantly to maintain control of the vehicle and ensure safety. Reducing speed by 20 to 50 percent allows drivers to react more effectively to changing road conditions and increases the time available to respond to potential hazards, such as decreased visibility or slippery surfaces. This range is a balanced approach that acknowledges that while you need to slow down considerably, you also have to maintain enough speed to keep traction and control, especially in severe but not extreme conditions.

Reducing speed too much could lead to other issues, such as losing momentum in snowy conditions or causing confusion among other drivers. Therefore, the guidance to reduce speed by 20 to 50 percent strikes a practical compromise that enhances safety without impairing driving ability.