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