If you double distance with speed constant, what happens to time?

If you double distance with speed constant, what happens to time?

• A. It halves
• B. It stays the same
• C. It doubles
• D. It quadruples

Answer: (C)

Time is proportional to distance when speed stays constant. Since speed = distance ÷ time, fixing speed means time = distance ÷ speed, so time grows in direct proportion to distance. If you double the distance while keeping the same speed, you must travel twice as far in the same rate, so it takes twice as long. For example, at a steady pace, going 3 miles takes 1 hour; going 6 miles at the same pace takes 2 hours. That’s why the time doubles. The other ideas would require changing the speed or a different relationship between distance and time.

Time is proportional to distance when speed stays constant. Since speed = distance ÷ time, fixing speed means time = distance ÷ speed, so time grows in direct proportion to distance. If you double the distance while keeping the same speed, you must travel twice as far in the same rate, so it takes twice as long. For example, at a steady pace, going 3 miles takes 1 hour; going 6 miles at the same pace takes 2 hours. That’s why the time doubles. The other ideas would require changing the speed or a different relationship between distance and time.