# A simple Question. How much “faster” is A than B as a percentage figure?

A simple question

If two people complete the same task, and Person A completes the task in 10 minutes, Person B in 8 minutes, what figures can/should be quoted in terms of how much quicker A is than B?

1. Person B completed the task in 80% of the time it took Person A to complete the task. Therefore Person B is 20% faster?

2. Person A took 125% of the time Person B took, so Person B is 25% faster?

So Person A completes a task in 100 minutes.

Using method 1, Person B will complete in 80% * 100 minutes = 80 minutes Using method 2, Person B will complete in 100 / 125% = 80 minutes

Obviously no difference, but what should be quoted? When manufacturers of various devices quote, this device is 20% faster than our rivals, what are they usually referring to?

• In (1), you should say that B took 20% less time than A. In (2), you should say that A took 25% more time than B. It might be okay to say that B is 20% faster than A, or that A is 25% slower than B. But you can't just switch the adjectives and keep the numbers, that's misleading. – MPW Jun 22 '14 at 12:45