Considering fractions might help you understand where he's coming from. If you say something is "0.5 times as long as a one meter thing" you would expect it to

Considering fractions might help you understand where he's coming from. If you say something is "0.5 times as long as a one meter thing" you would expect it to be 0.5 meters, but if it's "0.5 times longer than a one meter thing", you would expect it to be 1.5 meters. The same logic applies when you ditch fractions and use integers.